diff --git a/frontend/src/i18n.ts b/frontend/src/i18n.ts
index 737761f..b98a846 100644
--- a/frontend/src/i18n.ts
+++ b/frontend/src/i18n.ts
@@ -236,7 +236,8 @@ export const i18nData = {
       "Collection created successfully": "合集创建成功",
       "Collection deleted successfully": "合集删除成功",
       "Remove Resource": "移除资源",
-      "Are you sure you want to remove this resource?": "您确定要移除此资源吗？",
+      "Are you sure you want to remove this resource?":
+        "您确定要移除此资源吗？",
       "Resource deleted successfully": "资源移除成功",
       "Edit Collection": "编辑合集",
       "Edit successful": "编辑成功",
@@ -250,7 +251,9 @@ export const i18nData = {
       "Update File Info": "更新文件信息",
       "File info updated successfully": "文件信息更新成功",
       "File URL": "文件URL",
-      "You do not have permission to upload files, please contact the administrator.": "您没有上传文件的权限，请联系管理员。",
+      "You do not have permission to upload files, please contact the administrator.":
+        "您没有上传文件的权限，请联系管理员。",
+      "Private": "私有",
     },
   },
   "zh-TW": {
@@ -490,7 +493,8 @@ export const i18nData = {
       "Collection created successfully": "合集創建成功",
       "Collection deleted successfully": "合集刪除成功",
       "Remove Resource": "移除資源",
-      "Are you sure you want to remove this resource?": "您確定要移除此資源嗎？",
+      "Are you sure you want to remove this resource?":
+        "您確定要移除此資源嗎？",
       "Resource deleted successfully": "資源移除成功",
       "Edit Collection": "編輯合集",
       "Edit successful": "編輯成功",
@@ -504,7 +508,9 @@ export const i18nData = {
       "Update File Info": "更新檔案信息",
       "File info updated successfully": "檔案信息更新成功",
       "File URL": "檔案URL",
-      "You do not have permission to upload files, please contact the administrator.": "您沒有上傳檔案的權限，請聯繫管理員。",
+      "You do not have permission to upload files, please contact the administrator.":
+        "您沒有上傳檔案的權限，請聯繫管理員。",
+      "Private": "私有",
     },
   },
 };
diff --git a/frontend/src/network/models.ts b/frontend/src/network/models.ts
index 78a6d1f..f6582c8 100644
--- a/frontend/src/network/models.ts
+++ b/frontend/src/network/models.ts
@@ -199,4 +199,5 @@ export interface Collection {
   user: User;
   resources_count: number;
   images: Image[];
+  isPublic: boolean;
 }
diff --git a/frontend/src/network/network.ts b/frontend/src/network/network.ts
index 1502948..0671620 100644
--- a/frontend/src/network/network.ts
+++ b/frontend/src/network/network.ts
@@ -693,11 +693,13 @@ class Network {
   async createCollection(
     title: string,
     article: string,
+    isPublic: boolean,
   ): Promise<Response<Collection>> {
     return this._callApi(() =>
       axios.postForm(`${this.apiBaseUrl}/collection/create`, {
         title,
         article,
+        public: isPublic,
       }),
     );
   }
@@ -706,12 +708,14 @@ class Network {
     id: number,
     title: string,
     article: string,
+    isPublic: boolean,
   ): Promise<Response<any>> {
     return this._callApi(() =>
       axios.postForm(`${this.apiBaseUrl}/collection/update`, {
         id,
         title,
         article,
+        public: isPublic,
       }),
     );
   }
diff --git a/frontend/src/pages/collection_page.tsx b/frontend/src/pages/collection_page.tsx
index 25d9182..e8c3c32 100644
--- a/frontend/src/pages/collection_page.tsx
+++ b/frontend/src/pages/collection_page.tsx
@@ -6,10 +6,11 @@ import { Collection } from "../network/models";
 import Markdown from "react-markdown";
 import ResourcesView from "../components/resources_view";
 import Loading from "../components/loading";
-import { MdOutlineDelete, MdOutlineEdit } from "react-icons/md";
+import { MdOutlineAdd, MdOutlineDelete, MdOutlineEdit } from "react-icons/md";
 import { app } from "../app";
 import { useTranslation } from "../utils/i18n";
 import Button from "../components/button";
+import Badge from "../components/badge";
 
 export default function CollectionPage() {
   const { id } = useParams<{ id: string }>();
@@ -54,7 +55,7 @@ export default function CollectionPage() {
   useEffect(() => {
     if (!collection) return;
     document.title = collection.title;
-  }, [collection])
+  }, [collection]);
 
   const toBeDeletedRID = useRef<number | null>(null);
 
@@ -160,6 +161,12 @@ export default function CollectionPage() {
               </button>
             </>
           )}
+          <span className="flex-1" />
+          {!collection.isPublic && (
+            <Badge className="badge-soft badge-error text-xs mr-2">
+              <MdOutlineAdd size={16} className="inline-block" /> {t("Private")}
+            </Badge>
+          )}
         </div>
       </div>
       <ResourcesView
@@ -275,6 +282,7 @@ function EditCollectionDialog({
 }) {
   const [editTitle, setEditTitle] = useState(collection.title);
   const [editArticle, setEditArticle] = useState(collection.article);
+  const [editIsPublic, setEditIsPublic] = useState(collection.isPublic);
   const [editLoading, setEditLoading] = useState(false);
 
   const { t } = useTranslation();
@@ -292,6 +300,7 @@ function EditCollectionDialog({
       collection.id,
       editTitle,
       editArticle,
+      editIsPublic,
     );
     setEditLoading(false);
     if (res.success) {
@@ -300,7 +309,12 @@ function EditCollectionDialog({
       if (getRes.success) {
         onSaved(getRes.data!);
       } else {
-        onSaved({ ...collection, title: editTitle, article: editArticle });
+        onSaved({
+          ...collection,
+          title: editTitle,
+          article: editArticle,
+          isPublic: editIsPublic,
+        });
       }
     } else {
       showToast({
@@ -325,11 +339,21 @@ function EditCollectionDialog({
         />
         <label className="block mb-1">{t("Description")}</label>
         <textarea
-          className="textarea w-full min-h-32"
+          className="textarea w-full min-h-32 mb-2"
           value={editArticle}
           onChange={(e) => setEditArticle(e.target.value)}
           disabled={editLoading}
         />
+        <label className="flex items-center mb-4">
+          <input
+            type="checkbox"
+            checked={editIsPublic}
+            onChange={(e) => setEditIsPublic(e.target.checked)}
+            className="checkbox mr-2"
+            disabled={editLoading}
+          />
+          {t("Public")}
+        </label>
         <div className="modal-action">
           <button className="btn" onClick={onClose} disabled={editLoading}>
             {t("Cancel")}
diff --git a/frontend/src/pages/create_collection_page.tsx b/frontend/src/pages/create_collection_page.tsx
index a9db067..08b566e 100644
--- a/frontend/src/pages/create_collection_page.tsx
+++ b/frontend/src/pages/create_collection_page.tsx
@@ -8,6 +8,7 @@ import { useNavigate } from "react-router";
 export default function CreateCollectionPage() {
   const [title, setTitle] = useState<string>("");
   const [article, setArticle] = useState<string>("");
+  const [isPublic, setIsPublic] = useState<boolean>(true);
   const [isLoading, setLoading] = useState(false);
   const [isUploadingimage, setUploadingImage] = useState(false);
   const { t } = useTranslation();
@@ -73,7 +74,7 @@ export default function CreateCollectionPage() {
       return;
     }
     setLoading(true);
-    const res = await network.createCollection(title, article);
+    const res = await network.createCollection(title, article, isPublic);
     if (res.success) {
       showToast({
         message: t("Collection created successfully"),
@@ -110,6 +111,17 @@ export default function CreateCollectionPage() {
           onChange={(e) => setArticle(e.target.value)}
           className="textarea mt-1 w-full min-h-80"
         />
+        <div className="mt-4">
+          <label className="flex items-center">
+            <input
+              type="checkbox"
+              checked={isPublic}
+              onChange={(e) => setIsPublic(e.target.checked)}
+              className="checkbox mr-2"
+            />
+            {t("Public")}
+          </label>
+        </div>
       </div>
       <div className={"flex items-center mt-4"}>
         <button
diff --git a/frontend/src/pages/resource_details_page.tsx b/frontend/src/pages/resource_details_page.tsx
index ca8c005..a495c8a 100644
--- a/frontend/src/pages/resource_details_page.tsx
+++ b/frontend/src/pages/resource_details_page.tsx
@@ -218,24 +218,25 @@ export default function ResourcePage() {
         </button>
         <Tags tags={resource.tags} />
         <p className={"px-3 mt-2"}>
-          {resource.links && resource.links.map((l) => {
-            return (
-              <a href={l.url} target={"_blank"}>
-                <span
-                  className={
-                    "py-1 px-3 inline-flex items-center m-1 border border-base-300 bg-base-100 opacity-90 rounded-2xl hover:bg-base-200 transition-colors cursor-pointer select-none"
-                  }
-                >
-                  {l.url.includes("steampowered.com") ? (
-                    <BiLogoSteam size={20} />
-                  ) : (
-                    <MdOutlineLink size={20} />
-                  )}
-                  <span className={"ml-2 text-sm"}>{l.label}</span>
-                </span>
-              </a>
-            );
-          })}
+          {resource.links &&
+            resource.links.map((l) => {
+              return (
+                <a href={l.url} target={"_blank"}>
+                  <span
+                    className={
+                      "py-1 px-3 inline-flex items-center m-1 border border-base-300 bg-base-100 opacity-90 rounded-2xl hover:bg-base-200 transition-colors cursor-pointer select-none"
+                    }
+                  >
+                    {l.url.includes("steampowered.com") ? (
+                      <BiLogoSteam size={20} />
+                    ) : (
+                      <MdOutlineLink size={20} />
+                    )}
+                    <span className={"ml-2 text-sm"}>{l.label}</span>
+                  </span>
+                </a>
+              );
+            })}
           <CollectionDialog rid={resource.id} />
         </p>
 
@@ -1637,7 +1638,7 @@ function CollectionDialog({ rid }: { rid: number }) {
   };
 
   if (!app.isLoggedIn()) {
-    return <></>
+    return <></>;
   }
 
   return (
@@ -1683,13 +1684,16 @@ function CollectionDialog({ rid }: { rid: number }) {
             />
           )}
           <div className="modal-action">
-            <Button className="btn-ghost" onClick={() => {
-              const dialog = document.getElementById(
-                "collection_dialog",
-              ) as HTMLDialogElement;
-              dialog.close();
-              navigate("/create-collection");
-            }}>
+            <Button
+              className="btn-ghost"
+              onClick={() => {
+                const dialog = document.getElementById(
+                  "collection_dialog",
+                ) as HTMLDialogElement;
+                dialog.close();
+                navigate("/create-collection");
+              }}
+            >
               <div className="flex items-center">
                 <MdOutlineAdd size={20} className={"inline-block mr-1"} />
                 {t("Create")}
diff --git a/frontend/src/pages/user_page.tsx b/frontend/src/pages/user_page.tsx
index f73f09e..bbac8aa 100644
--- a/frontend/src/pages/user_page.tsx
+++ b/frontend/src/pages/user_page.tsx
@@ -413,15 +413,17 @@ function Collections({ username }: { username?: string }) {
           onChange={(e) => delayedSetSearchKeyword(e.target.value)}
         />
         <span className="flex-1" />
-        {username == app.user?.username && <button
-          className="btn btn-primary btn-soft"
-          onClick={() => {
-            navigate("/create-collection");
-          }}
-        >
-          <MdOutlineAdd size={20} className="inline-block mr-1" />
-          {t("Create")}
-        </button>}
+        {username == app.user?.username && (
+          <button
+            className="btn btn-primary btn-soft"
+            onClick={() => {
+              navigate("/create-collection");
+            }}
+          >
+            <MdOutlineAdd size={20} className="inline-block mr-1" />
+            {t("Create")}
+          </button>
+        )}
       </div>
       <CollectionsList
         username={username}
@@ -522,6 +524,12 @@ function CollectionCard({ collection }: { collection: Collection }) {
           <MdOutlinePhotoAlbum size={16} className="inline-block" />
           {collection.resources_count} {t("Resources")}
         </Badge>
+        <span className="flex-1" />
+        {!collection.isPublic && (
+          <Badge className="badge-soft badge-error text-xs mr-2">
+            <MdOutlineAdd size={16} className="inline-block" /> {t("Private")}
+          </Badge>
+        )}
       </div>
     </div>
   );
diff --git a/server/api/collection.go b/server/api/collection.go
index 52701d1..d274e91 100644
--- a/server/api/collection.go
+++ b/server/api/collection.go
@@ -15,11 +15,16 @@ func handleCreateCollection(c fiber.Ctx) error {
 	}
 	title := c.FormValue("title")
 	article := c.FormValue("article")
+	publicStr := c.FormValue("public")
+	public := false
+	if publicStr == "true" || publicStr == "1" {
+		public = true
+	}
 	if title == "" || article == "" {
 		return model.NewRequestError("Title and article are required")
 	}
 	host := c.Hostname()
-	col, err := service.CreateCollection(uid, title, article, host)
+	col, err := service.CreateCollection(uid, title, article, host, public)
 	if err != nil {
 		return err
 	}
@@ -38,6 +43,11 @@ func handleUpdateCollection(c fiber.Ctx) error {
 	idStr := c.FormValue("id")
 	title := c.FormValue("title")
 	article := c.FormValue("article")
+	publicStr := c.FormValue("public")
+	public := false
+	if publicStr == "true" || publicStr == "1" {
+		public = true
+	}
 	if idStr == "" || title == "" || article == "" {
 		return model.NewRequestError("ID, title and article are required")
 	}
@@ -46,7 +56,7 @@ func handleUpdateCollection(c fiber.Ctx) error {
 		return model.NewRequestError("Invalid collection ID")
 	}
 	host := c.Hostname()
-	if err := service.UpdateCollection(uid, uint(id), title, article, host); err != nil {
+	if err := service.UpdateCollection(uid, uint(id), title, article, host, public); err != nil {
 		return err
 	}
 	return c.Status(fiber.StatusOK).JSON(model.Response[any]{
@@ -83,7 +93,11 @@ func handleGetCollection(c fiber.Ctx) error {
 	if err != nil {
 		return model.NewRequestError("Invalid collection ID")
 	}
-	col, err := service.GetCollectionByID(uint(id))
+
+	// Get viewer UID (0 if not authenticated)
+	viewerUID, _ := c.Locals("uid").(uint)
+
+	col, err := service.GetCollectionByID(uint(id), viewerUID)
 	if err != nil {
 		return err
 	}
@@ -104,7 +118,11 @@ func handleListUserCollections(c fiber.Ctx) error {
 	if username == "" {
 		return model.NewRequestError("Username is required")
 	}
-	cols, total, err := service.ListUserCollections(username, page)
+
+	// Get viewer UID (0 if not authenticated)
+	viewerUID, _ := c.Locals("uid").(uint)
+
+	cols, total, err := service.ListUserCollections(username, page, viewerUID)
 	if err != nil {
 		return err
 	}
@@ -127,7 +145,11 @@ func handleListCollectionResources(c fiber.Ctx) error {
 	if err != nil || page < 1 {
 		page = 1
 	}
-	res, total, err := service.ListCollectionResources(uint(id), page)
+
+	// Get viewer UID (0 if not authenticated)
+	viewerUID, _ := c.Locals("uid").(uint)
+
+	res, total, err := service.ListCollectionResources(uint(id), page, viewerUID)
 	if err != nil {
 		return err
 	}
@@ -209,7 +231,11 @@ func handleSearchUserCollections(c fiber.Ctx) error {
 			excludedRID = uint(rid)
 		}
 	}
-	cols, err := service.SearchUserCollections(username, keyword, excludedRID)
+
+	// Get viewer UID (0 if not authenticated)
+	viewerUID, _ := c.Locals("uid").(uint)
+
+	cols, err := service.SearchUserCollections(username, keyword, excludedRID, viewerUID)
 	if err != nil {
 		return err
 	}
diff --git a/server/dao/collection.go b/server/dao/collection.go
index ecfb9e0..04503fb 100644
--- a/server/dao/collection.go
+++ b/server/dao/collection.go
@@ -6,13 +6,14 @@ import (
 	"gorm.io/gorm"
 )
 
-func CreateCollection(uid uint, title string, article string, images []uint) (model.Collection, error) {
+func CreateCollection(uid uint, title string, article string, images []uint, public bool) (model.Collection, error) {
 	var collection model.Collection
 	err := db.Transaction(func(tx *gorm.DB) error {
 		collection = model.Collection{
 			UserID:  uid,
 			Title:   title,
 			Article: article,
+			Public:  public, // 新增
 		}
 
 		if err := tx.Create(&collection).Error; err != nil {
@@ -32,7 +33,7 @@ func CreateCollection(uid uint, title string, article string, images []uint) (mo
 	return collection, nil
 }
 
-func UpdateCollection(id uint, title string, article string, images []uint) error {
+func UpdateCollection(id uint, title string, article string, images []uint, public bool) error {
 	return db.Transaction(func(tx *gorm.DB) error {
 		collection := &model.Collection{
 			Model: gorm.Model{
@@ -40,6 +41,7 @@ func UpdateCollection(id uint, title string, article string, images []uint) erro
 			},
 			Title:   title,
 			Article: article,
+			Public:  public, // 新增
 		}
 
 		if err := tx.Model(collection).Updates(collection).Error; err != nil {
@@ -142,19 +144,22 @@ func GetCollectionByID(id uint) (*model.Collection, error) {
 	return collection, nil
 }
 
-func ListUserCollections(uid uint, page int, pageSize int) ([]*model.Collection, int64, error) {
+func ListUserCollections(uid uint, page int, pageSize int, showPrivate bool) ([]*model.Collection, int64, error) {
 	var collections []*model.Collection
 	var total int64
 
-	if err := db.Model(&model.Collection{}).Where("user_id = ?", uid).Count(&total).Error; err != nil {
+	query := db.Model(&model.Collection{}).Where("user_id = ?", uid)
+	if !showPrivate {
+		query = query.Where("public = ?", true)
+	}
+
+	if err := query.Count(&total).Error; err != nil {
 		return nil, 0, err
 	}
 
-	if err := db.
-		Model(&model.Collection{}).
+	if err := query.
 		Preload("Images").
 		Preload("Resources").
-		Where("user_id = ?", uid).
 		Offset((page - 1) * pageSize).
 		Limit(pageSize).
 		Find(&collections).Error; err != nil {
@@ -196,12 +201,16 @@ func ListCollectionResources(collectionID uint, page int, pageSize int) ([]*mode
 
 // SearchUserCollections searches for collections by user ID and keyword limited to 10 results.
 // excludedRID: if >0, only return collections not containing this resource.
-func SearchUserCollections(uid uint, keyword string, excludedRID uint) ([]*model.Collection, error) {
+func SearchUserCollections(uid uint, keyword string, excludedRID uint, showPrivate bool) ([]*model.Collection, error) {
 	var collections []*model.Collection
 
 	query := db.Model(&model.Collection{}).
 		Where("user_id = ?", uid)
 
+	if !showPrivate {
+		query = query.Where("public = ?", true)
+	}
+
 	if keyword != "" {
 		query = query.Where("title LIKE ?", "%"+keyword+"%")
 	}
diff --git a/server/model/collection.go b/server/model/collection.go
index f962500..8ba5606 100644
--- a/server/model/collection.go
+++ b/server/model/collection.go
@@ -11,6 +11,7 @@ type Collection struct {
 	ResourcesCount int        `gorm:"default:0"`
 	Images         []Image    `gorm:"many2many:collection_images;"`
 	Resources      []Resource `gorm:"many2many:collection_resources;"`
+	Public         bool       `gorm:"default:false"` // 新增公开/私有字段
 }
 
 type CollectionView struct {
@@ -20,6 +21,7 @@ type CollectionView struct {
 	User           UserView `json:"user"`
 	ResourcesCount int      `json:"resources_count"`
 	Images         []Image  `json:"images"`
+	IsPublic       bool     `json:"isPublic"` // 新增公开/私有字段
 }
 
 func (c Collection) ToView() *CollectionView {
@@ -30,5 +32,6 @@ func (c Collection) ToView() *CollectionView {
 		User:           c.User.ToView(),
 		ResourcesCount: c.ResourcesCount,
 		Images:         c.Images,
+		IsPublic:       c.Public, // 新增
 	}
 }
diff --git a/server/service/collection.go b/server/service/collection.go
index 84bd3b7..c133d6a 100644
--- a/server/service/collection.go
+++ b/server/service/collection.go
@@ -6,11 +6,11 @@ import (
 )
 
 // Create a new collection.
-func CreateCollection(uid uint, title, article string, host string) (*model.CollectionView, error) {
+func CreateCollection(uid uint, title, article string, host string, public bool) (*model.CollectionView, error) {
 	if uid == 0 || title == "" || article == "" {
 		return nil, model.NewRequestError("invalid parameters")
 	}
-	c, err := dao.CreateCollection(uid, title, article, findImagesInContent(article, host))
+	c, err := dao.CreateCollection(uid, title, article, findImagesInContent(article, host), public)
 	if err != nil {
 		return nil, err
 	}
@@ -19,7 +19,7 @@ func CreateCollection(uid uint, title, article string, host string) (*model.Coll
 }
 
 // Update an existing collection with user validation.
-func UpdateCollection(uid, id uint, title, article string, host string) error {
+func UpdateCollection(uid, id uint, title, article string, host string, public bool) error {
 	if uid == 0 || id == 0 || title == "" || article == "" {
 		return model.NewRequestError("invalid parameters")
 	}
@@ -30,7 +30,7 @@ func UpdateCollection(uid, id uint, title, article string, host string) error {
 	if collection.UserID != uid {
 		return model.NewUnAuthorizedError("user does not have permission to update this collection")
 	}
-	return dao.UpdateCollection(id, title, article, findImagesInContent(article, host))
+	return dao.UpdateCollection(id, title, article, findImagesInContent(article, host), public)
 }
 
 // Delete a collection by ID.
@@ -83,7 +83,7 @@ func RemoveResourceFromCollection(uid, collectionID, resourceID uint) error {
 }
 
 // Get a collection by ID.
-func GetCollectionByID(id uint) (*model.CollectionView, error) {
+func GetCollectionByID(id uint, viewerUID uint) (*model.CollectionView, error) {
 	if id == 0 {
 		return nil, model.NewRequestError("invalid collection id")
 	}
@@ -91,11 +91,17 @@ func GetCollectionByID(id uint) (*model.CollectionView, error) {
 	if err != nil {
 		return nil, err
 	}
+
+	// Check if collection is private and viewer is not the owner
+	if !c.Public && c.UserID != viewerUID {
+		return nil, model.NewUnAuthorizedError("you do not have permission to view this private collection")
+	}
+
 	return c.ToView(), nil
 }
 
 // List collections of a user with pagination.
-func ListUserCollections(username string, page int) ([]*model.CollectionView, int64, error) {
+func ListUserCollections(username string, page int, viewerUID uint) ([]*model.CollectionView, int64, error) {
 	if username == "" || page < 1 {
 		return nil, 0, model.NewRequestError("invalid parameters")
 	}
@@ -104,7 +110,11 @@ func ListUserCollections(username string, page int) ([]*model.CollectionView, in
 		return nil, 0, err
 	}
 	uid := user.ID
-	collections, total, err := dao.ListUserCollections(uid, page, pageSize)
+
+	// Check if viewer can see private collections (only owner can see their private collections)
+	showPrivate := uid == viewerUID
+
+	collections, total, err := dao.ListUserCollections(uid, page, pageSize, showPrivate)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -116,10 +126,21 @@ func ListUserCollections(username string, page int) ([]*model.CollectionView, in
 }
 
 // List resources in a collection with pagination.
-func ListCollectionResources(collectionID uint, page int) ([]*model.ResourceView, int64, error) {
+func ListCollectionResources(collectionID uint, page int, viewerUID uint) ([]*model.ResourceView, int64, error) {
 	if collectionID == 0 || page < 1 {
 		return nil, 0, model.NewRequestError("invalid parameters")
 	}
+
+	// Check collection privacy first
+	collection, err := dao.GetCollectionByID(collectionID)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	if !collection.Public && collection.UserID != viewerUID {
+		return nil, 0, model.NewUnAuthorizedError("you do not have permission to view this private collection")
+	}
+
 	resources, total, err := dao.ListCollectionResources(collectionID, page, pageSize)
 	if err != nil {
 		return nil, 0, err
@@ -134,7 +155,7 @@ func ListCollectionResources(collectionID uint, page int) ([]*model.ResourceView
 
 // Search user collections by keyword, limited to 10 results.
 // excludedRID: if >0, only return collections not containing this resource.
-func SearchUserCollections(username string, keyword string, excludedRID uint) ([]*model.CollectionView, error) {
+func SearchUserCollections(username string, keyword string, excludedRID uint, viewerUID uint) ([]*model.CollectionView, error) {
 	if username == "" {
 		return nil, model.NewRequestError("invalid parameters")
 	}
@@ -143,7 +164,11 @@ func SearchUserCollections(username string, keyword string, excludedRID uint) ([
 		return nil, err
 	}
 	uid := user.ID
-	collections, err := dao.SearchUserCollections(uid, keyword, excludedRID)
+
+	// Check if viewer can see private collections
+	showPrivate := uid == viewerUID
+
+	collections, err := dao.SearchUserCollections(uid, keyword, excludedRID, showPrivate)
 	if err != nil {
 		return nil, err
 	}