diff --git a/backend/app/http/tenant/media_asset_admin.go b/backend/app/http/tenant/media_asset_admin.go
index 141a950..de68554 100644
--- a/backend/app/http/tenant/media_asset_admin.go
+++ b/backend/app/http/tenant/media_asset_admin.go
@@ -159,3 +159,36 @@ func (*mediaAssetAdmin) uploadComplete(
 
 	return services.MediaAsset.AdminUploadComplete(ctx.Context(), tenant.ID, tenantUser.UserID, assetID, form, time.Now())
 }
+
+// adminDelete
+//
+//	@Summary	删除媒体资源（租户管理，软删）
+//	@Tags		Tenant
+//	@Accept		json
+//	@Produce	json
+//	@Param		tenantCode	path		string	true	"Tenant Code"
+//	@Param		assetID		path		int64	true	"AssetID"
+//	@Success	200			{object}	models.MediaAsset
+//
+//	@Router		/t/:tenantCode/v1/admin/media_assets/:assetID [delete]
+//	@Bind		tenant local key(tenant)
+//	@Bind		tenantUser local key(tenant_user)
+//	@Bind		assetID path
+func (*mediaAssetAdmin) adminDelete(
+	ctx fiber.Ctx,
+	tenant *models.Tenant,
+	tenantUser *models.TenantUser,
+	assetID int64,
+) (*models.MediaAsset, error) {
+	if err := requireTenantAdmin(tenantUser); err != nil {
+		return nil, err
+	}
+
+	log.WithFields(log.Fields{
+		"tenant_id": tenant.ID,
+		"user_id":   tenantUser.UserID,
+		"asset_id":  assetID,
+	}).Info("tenant.admin.media_assets.delete")
+
+	return services.MediaAsset.AdminDelete(ctx.Context(), tenant.ID, tenantUser.UserID, assetID, time.Now())
+}
diff --git a/backend/app/http/tenant/routes.gen.go b/backend/app/http/tenant/routes.gen.go
index 8dc6980..c4412a4 100644
--- a/backend/app/http/tenant/routes.gen.go
+++ b/backend/app/http/tenant/routes.gen.go
@@ -134,6 +134,13 @@ func (r *Routes) Register(router fiber.Router) {
 		Query[dto.MyLedgerListFilter]("filter"),
 	))
 	// Register routes for controller: mediaAssetAdmin
+	r.log.Debugf("Registering route: Delete /t/:tenantCode/v1/admin/media_assets/:assetID -> mediaAssetAdmin.adminDelete")
+	router.Delete("/t/:tenantCode/v1/admin/media_assets/:assetID"[len(r.Path()):], DataFunc3(
+		r.mediaAssetAdmin.adminDelete,
+		Local[*models.Tenant]("tenant"),
+		Local[*models.TenantUser]("tenant_user"),
+		PathParam[int64]("assetID"),
+	))
 	r.log.Debugf("Registering route: Get /t/:tenantCode/v1/admin/media_assets -> mediaAssetAdmin.adminList")
 	router.Get("/t/:tenantCode/v1/admin/media_assets"[len(r.Path()):], DataFunc3(
 		r.mediaAssetAdmin.adminList,
diff --git a/backend/app/services/content.go b/backend/app/services/content.go
index 1497603..e8f9e0a 100644
--- a/backend/app/services/content.go
+++ b/backend/app/services/content.go
@@ -187,6 +187,34 @@ func (s *content) AttachAsset(ctx context.Context, tenantID, userID, contentID,
 		"sort":       sort,
 	}).Info("services.content.attach_asset")
 
+	// 约束：只能绑定本租户内、且已处理完成（ready）的资源；避免未完成处理的资源对外可见。
+	tblContent, queryContent := models.ContentQuery.QueryContext(ctx)
+	if _, err := queryContent.Where(
+		tblContent.TenantID.Eq(tenantID),
+		tblContent.ID.Eq(contentID),
+	).First(); err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, errorx.ErrRecordNotFound.WithMsg("content not found")
+		}
+		return nil, err
+	}
+
+	tblAsset, queryAsset := models.MediaAssetQuery.QueryContext(ctx)
+	asset, err := queryAsset.Where(
+		tblAsset.TenantID.Eq(tenantID),
+		tblAsset.ID.Eq(assetID),
+		tblAsset.DeletedAt.IsNull(),
+	).First()
+	if err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, errorx.ErrRecordNotFound.WithMsg("media asset not found")
+		}
+		return nil, err
+	}
+	if asset.Status != consts.MediaAssetStatusReady {
+		return nil, errorx.ErrPreconditionFailed.WithMsg("media asset not ready")
+	}
+
 	m := &models.ContentAsset{
 		TenantID:  tenantID,
 		UserID:    userID,
diff --git a/backend/app/services/media_asset.go b/backend/app/services/media_asset.go
index bf6b7ad..a3003df 100644
--- a/backend/app/services/media_asset.go
+++ b/backend/app/services/media_asset.go
@@ -31,6 +31,19 @@ import (
 //	@provider
 type mediaAsset struct{}
 
+func mediaAssetTransitionAllowed(from, to consts.MediaAssetStatus) bool {
+	switch from {
+	case consts.MediaAssetStatusUploaded:
+		return to == consts.MediaAssetStatusProcessing
+	case consts.MediaAssetStatusProcessing:
+		return to == consts.MediaAssetStatusReady || to == consts.MediaAssetStatusFailed
+	case consts.MediaAssetStatusReady, consts.MediaAssetStatusFailed:
+		return to == consts.MediaAssetStatusDeleted
+	default:
+		return false
+	}
+}
+
 func newObjectKey(tenantID, userID int64, assetType consts.MediaAssetType, now time.Time) (string, error) {
 	// object_key 作为存储定位的关键字段：必须由服务端生成，避免客户端路径注入与越权覆盖。
 	buf := make([]byte, 16) // 128-bit
@@ -200,6 +213,9 @@ func (s *mediaAsset) AdminUploadComplete(
 		}
 
 		// 状态迁移：uploaded -> processing
+		if !mediaAssetTransitionAllowed(m.Status, consts.MediaAssetStatusProcessing) {
+			return errorx.ErrStatusConflict.WithMsg("invalid media asset status transition")
+		}
 		if err := tx.Model(&models.MediaAsset{}).
 			Where("id = ?", m.ID).
 			Updates(map[string]any{
@@ -231,6 +247,215 @@ func (s *mediaAsset) AdminUploadComplete(
 	return &out, nil
 }
 
+// ProcessSuccess marks a processing asset as ready.
+// 用于异步处理链路（worker/job）回写处理结果；当前不暴露 HTTP 接口。
+func (s *mediaAsset) ProcessSuccess(
+	ctx context.Context,
+	tenantID, assetID int64,
+	metaPatch map[string]any,
+	now time.Time,
+) (*models.MediaAsset, error) {
+	if tenantID <= 0 || assetID <= 0 {
+		return nil, errorx.ErrInvalidParameter.WithMsg("tenant_id/asset_id must be > 0")
+	}
+	if now.IsZero() {
+		now = time.Now()
+	}
+
+	var out models.MediaAsset
+	err := _db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		var m models.MediaAsset
+		if err := tx.
+			Clauses(clause.Locking{Strength: "UPDATE"}).
+			Where("tenant_id = ? AND id = ?", tenantID, assetID).
+			First(&m).Error; err != nil {
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return errorx.ErrRecordNotFound.WithMsg("media asset not found")
+			}
+			return err
+		}
+		if m.DeletedAt.Valid || m.Status == consts.MediaAssetStatusDeleted {
+			return errorx.ErrPreconditionFailed.WithMsg("media asset deleted")
+		}
+		if m.Status == consts.MediaAssetStatusReady {
+			out = m
+			return nil
+		}
+		if !mediaAssetTransitionAllowed(m.Status, consts.MediaAssetStatusReady) {
+			return errorx.ErrStatusConflict.WithMsg("invalid media asset status transition")
+		}
+
+		meta := map[string]any{}
+		if len(m.Meta) > 0 {
+			_ = json.Unmarshal(m.Meta, &meta)
+		}
+		for k, v := range metaPatch {
+			if strings.TrimSpace(k) == "" {
+				continue
+			}
+			meta[k] = v
+		}
+		meta["processed_at"] = now.UTC().Format(time.RFC3339Nano)
+		metaBytes, _ := json.Marshal(meta)
+		if len(metaBytes) == 0 {
+			metaBytes = []byte("{}")
+		}
+
+		if err := tx.Model(&models.MediaAsset{}).
+			Where("id = ?", m.ID).
+			Updates(map[string]any{
+				"status":     consts.MediaAssetStatusReady,
+				"meta":       types.JSON(metaBytes),
+				"updated_at": now,
+			}).Error; err != nil {
+			return err
+		}
+		m.Status = consts.MediaAssetStatusReady
+		m.Meta = types.JSON(metaBytes)
+		m.UpdatedAt = now
+		out = m
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+// ProcessFailed marks a processing asset as failed.
+// 用于异步处理链路（worker/job）回写处理结果；当前不暴露 HTTP 接口。
+func (s *mediaAsset) ProcessFailed(
+	ctx context.Context,
+	tenantID, assetID int64,
+	reason string,
+	now time.Time,
+) (*models.MediaAsset, error) {
+	if tenantID <= 0 || assetID <= 0 {
+		return nil, errorx.ErrInvalidParameter.WithMsg("tenant_id/asset_id must be > 0")
+	}
+	if now.IsZero() {
+		now = time.Now()
+	}
+
+	var out models.MediaAsset
+	err := _db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		var m models.MediaAsset
+		if err := tx.
+			Clauses(clause.Locking{Strength: "UPDATE"}).
+			Where("tenant_id = ? AND id = ?", tenantID, assetID).
+			First(&m).Error; err != nil {
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return errorx.ErrRecordNotFound.WithMsg("media asset not found")
+			}
+			return err
+		}
+		if m.DeletedAt.Valid || m.Status == consts.MediaAssetStatusDeleted {
+			return errorx.ErrPreconditionFailed.WithMsg("media asset deleted")
+		}
+		if m.Status == consts.MediaAssetStatusFailed {
+			out = m
+			return nil
+		}
+		if !mediaAssetTransitionAllowed(m.Status, consts.MediaAssetStatusFailed) {
+			return errorx.ErrStatusConflict.WithMsg("invalid media asset status transition")
+		}
+
+		meta := map[string]any{}
+		if len(m.Meta) > 0 {
+			_ = json.Unmarshal(m.Meta, &meta)
+		}
+		if strings.TrimSpace(reason) != "" {
+			meta["failed_reason"] = strings.TrimSpace(reason)
+		}
+		meta["failed_at"] = now.UTC().Format(time.RFC3339Nano)
+		metaBytes, _ := json.Marshal(meta)
+		if len(metaBytes) == 0 {
+			metaBytes = []byte("{}")
+		}
+
+		if err := tx.Model(&models.MediaAsset{}).
+			Where("id = ?", m.ID).
+			Updates(map[string]any{
+				"status":     consts.MediaAssetStatusFailed,
+				"meta":       types.JSON(metaBytes),
+				"updated_at": now,
+			}).Error; err != nil {
+			return err
+		}
+		m.Status = consts.MediaAssetStatusFailed
+		m.Meta = types.JSON(metaBytes)
+		m.UpdatedAt = now
+		out = m
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+// AdminDelete soft-deletes a media asset (ready/failed -> deleted).
+func (s *mediaAsset) AdminDelete(ctx context.Context, tenantID, operatorUserID, assetID int64, now time.Time) (*models.MediaAsset, error) {
+	if tenantID <= 0 || operatorUserID <= 0 || assetID <= 0 {
+		return nil, errorx.ErrInvalidParameter.WithMsg("tenant_id/operator_user_id/asset_id must be > 0")
+	}
+	if now.IsZero() {
+		now = time.Now()
+	}
+
+	logrus.WithFields(logrus.Fields{
+		"tenant_id": tenantID,
+		"user_id":   operatorUserID,
+		"asset_id":  assetID,
+	}).Info("services.media_asset.admin.delete")
+
+	var out models.MediaAsset
+	err := _db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		var m models.MediaAsset
+		if err := tx.
+			Clauses(clause.Locking{Strength: "UPDATE"}).
+			Where("tenant_id = ? AND id = ?", tenantID, assetID).
+			First(&m).Error; err != nil {
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return errorx.ErrRecordNotFound.WithMsg("media asset not found")
+			}
+			return err
+		}
+
+		// 幂等：已删除直接返回。
+		if m.DeletedAt.Valid || m.Status == consts.MediaAssetStatusDeleted {
+			out = m
+			return nil
+		}
+
+		if !mediaAssetTransitionAllowed(m.Status, consts.MediaAssetStatusDeleted) {
+			return errorx.ErrStatusConflict.WithMsg("invalid media asset status transition")
+		}
+
+		if err := tx.Model(&models.MediaAsset{}).
+			Where("id = ?", m.ID).
+			Updates(map[string]any{
+				"status":     consts.MediaAssetStatusDeleted,
+				"updated_at": now,
+			}).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Delete(&m).Error; err != nil {
+			return err
+		}
+
+		m.Status = consts.MediaAssetStatusDeleted
+		m.UpdatedAt = now
+		out = m
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 // AdminPage 分页查询租户内媒体资源（租户管理）。
 func (s *mediaAsset) AdminPage(ctx context.Context, tenantID int64, filter *tenant_dto.AdminMediaAssetListFilter) (*requests.Pager, error) {
 	if tenantID <= 0 {
diff --git a/backend/docs/docs.go b/backend/docs/docs.go
index 12d4fe4..b0644ed 100644
--- a/backend/docs/docs.go
+++ b/backend/docs/docs.go
@@ -1131,6 +1131,43 @@ const docTemplate = `{
                         }
                     }
                 }
+            },
+            "delete": {
+                "consumes": [
+                    "application/json"
+                ],
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "Tenant"
+                ],
+                "summary": "删除媒体资源（租户管理，软删）",
+                "parameters": [
+                    {
+                        "type": "string",
+                        "description": "Tenant Code",
+                        "name": "tenantCode",
+                        "in": "path",
+                        "required": true
+                    },
+                    {
+                        "type": "integer",
+                        "format": "int64",
+                        "description": "AssetID",
+                        "name": "assetID",
+                        "in": "path",
+                        "required": true
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK",
+                        "schema": {
+                            "$ref": "#/definitions/models.MediaAsset"
+                        }
+                    }
+                }
             }
         },
         "/t/{tenantCode}/v1/admin/media_assets/{assetID}/upload_complete": {
diff --git a/backend/docs/swagger.json b/backend/docs/swagger.json
index 769d7c2..18efe2d 100644
--- a/backend/docs/swagger.json
+++ b/backend/docs/swagger.json
@@ -1125,6 +1125,43 @@
                         }
                     }
                 }
+            },
+            "delete": {
+                "consumes": [
+                    "application/json"
+                ],
+                "produces": [
+                    "application/json"
+                ],
+                "tags": [
+                    "Tenant"
+                ],
+                "summary": "删除媒体资源（租户管理，软删）",
+                "parameters": [
+                    {
+                        "type": "string",
+                        "description": "Tenant Code",
+                        "name": "tenantCode",
+                        "in": "path",
+                        "required": true
+                    },
+                    {
+                        "type": "integer",
+                        "format": "int64",
+                        "description": "AssetID",
+                        "name": "assetID",
+                        "in": "path",
+                        "required": true
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "description": "OK",
+                        "schema": {
+                            "$ref": "#/definitions/models.MediaAsset"
+                        }
+                    }
+                }
             }
         },
         "/t/{tenantCode}/v1/admin/media_assets/{assetID}/upload_complete": {
diff --git a/backend/docs/swagger.yaml b/backend/docs/swagger.yaml
index e592f40..2259ffe 100644
--- a/backend/docs/swagger.yaml
+++ b/backend/docs/swagger.yaml
@@ -2002,6 +2002,31 @@ paths:
       tags:
       - Tenant
   /t/{tenantCode}/v1/admin/media_assets/{assetID}:
+    delete:
+      consumes:
+      - application/json
+      parameters:
+      - description: Tenant Code
+        in: path
+        name: tenantCode
+        required: true
+        type: string
+      - description: AssetID
+        format: int64
+        in: path
+        name: assetID
+        required: true
+        type: integer
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: OK
+          schema:
+            $ref: '#/definitions/models.MediaAsset'
+      summary: 删除媒体资源（租户管理，软删）
+      tags:
+      - Tenant
     get:
       consumes:
       - application/json
diff --git a/backend/tests/tenant.http b/backend/tests/tenant.http
index 19f1178..9ae8162 100644
--- a/backend/tests/tenant.http
+++ b/backend/tests/tenant.http
@@ -159,6 +159,11 @@ GET {{ host }}/t/{{ tenantCode }}/v1/admin/media_assets/{{ assetID }}
 Content-Type: application/json
 Authorization: Bearer {{ token }}
 
+### Tenant Admin - MediaAsset delete (soft delete; ready/failed only)
+DELETE {{ host }}/t/{{ tenantCode }}/v1/admin/media_assets/{{ assetID }}
+Content-Type: application/json
+Authorization: Bearer {{ token }}
+
 ### Tenant Admin - Attach asset to content (main/cover/preview)
 @assetID = 1
 POST {{ host }}/t/{{ tenantCode }}/v1/admin/contents/{{ contentID }}/assets