diff --git a/server/dao/resource.go b/server/dao/resource.go
index 802b29f..8b39af7 100644
--- a/server/dao/resource.go
+++ b/server/dao/resource.go
@@ -24,6 +24,10 @@ func CreateResource(r model.Resource) (model.Resource, error) {
 		}
 		for _, c := range characters {
 			c.ResourceID = r.ID
+			// If ImageID is 0, set it to nil to avoid foreign key constraint error
+			if c.ImageID != nil && *c.ImageID == 0 {
+				c.ImageID = nil
+			}
 			if err := tx.Create(&c).Error; err != nil {
 				return err
 			}
@@ -155,6 +159,10 @@ func UpdateResource(r model.Resource) error {
 			if shouldAdd {
 				c.ID = 0
 				c.ResourceID = r.ID
+				// If ImageID is 0, set it to nil to avoid foreign key constraint error
+				if c.ImageID != nil && *c.ImageID == 0 {
+					c.ImageID = nil
+				}
 				if err := tx.Create(&c).Error; err != nil {
 					return err
 				}
@@ -520,7 +528,14 @@ func CountResources() (int64, error) {
 
 // UpdateCharacterImage 更新角色的图片ID
 func UpdateCharacterImage(characterID, imageID uint) error {
-	result := db.Model(&model.Character{}).Where("id = ?", characterID).Update("image_id", imageID)
+	var updateValue interface{}
+	if imageID == 0 {
+		updateValue = nil
+	} else {
+		updateValue = imageID
+	}
+
+	result := db.Model(&model.Character{}).Where("id = ?", characterID).Update("image_id", updateValue)
 	if result.Error != nil {
 		return result.Error
 	}
diff --git a/server/model/character.go b/server/model/character.go
index d99635e..91cbca4 100644
--- a/server/model/character.go
+++ b/server/model/character.go
@@ -6,7 +6,7 @@ type Character struct {
 	Alias      []string `gorm:"serializer:json"`
 	CV         string   `gorm:"type:varchar(100)"`
 	Role       string   `gorm:"type:varchar(20);default:primary"`
-	ImageID    uint
+	ImageID    *uint
 	ResourceID uint
 	Image      *Image `gorm:"foreignKey:ImageID;constraint:OnUpdate:CASCADE,OnDelete:SET NULL;"`
 }
@@ -21,18 +21,29 @@ type CharacterView struct {
 }
 
 func (c *Character) ToView() *CharacterView {
+	var imageID uint
+	if c.ImageID != nil {
+		imageID = *c.ImageID
+	}
 	return &CharacterView{
 		Id:    c.ID,
 		Name:  c.Name,
 		Alias: c.Alias,
 		CV:    c.CV,
 		Role:  c.Role,
-		Image: c.ImageID,
+		Image: imageID,
 	}
 }
 
 func (c *Character) Equal(other *Character) bool {
-	if c.Name != other.Name || c.CV != other.CV || c.Role != other.Role || c.ImageID != other.ImageID {
+	if c.Name != other.Name || c.CV != other.CV || c.Role != other.Role {
+		return false
+	}
+	// Compare ImageID pointers
+	if (c.ImageID == nil) != (other.ImageID == nil) {
+		return false
+	}
+	if c.ImageID != nil && other.ImageID != nil && *c.ImageID != *other.ImageID {
 		return false
 	}
 	if len(c.Alias) != len(other.Alias) {
diff --git a/server/service/resource.go b/server/service/resource.go
index 1b7f5c4..6a5358d 100644
--- a/server/service/resource.go
+++ b/server/service/resource.go
@@ -89,12 +89,16 @@ func CreateResource(uid uint, params *ResourceParams) (uint, error) {
 		if role == "" {
 			role = "primary"
 		}
+		var imageID *uint
+		if c.Image != 0 {
+			imageID = &c.Image
+		}
 		characters[i] = model.Character{
 			Name:    c.Name,
 			Alias:   c.Alias,
 			CV:      c.CV,
 			Role:    role,
-			ImageID: c.Image,
+			ImageID: imageID,
 		}
 	}
 	r := model.Resource{
@@ -512,12 +516,16 @@ func UpdateResource(uid, rid uint, params *ResourceParams) error {
 		if role == "" {
 			role = "primary"
 		}
+		var imageID *uint
+		if c.Image != 0 {
+			imageID = &c.Image
+		}
 		characters[i] = model.Character{
 			Name:    c.Name,
 			Alias:   c.Alias,
 			CV:      c.CV,
 			Role:    role,
-			ImageID: c.Image,
+			ImageID: imageID,
 		}
 	}