diff --git a/server/app/goauto/task/image_search_link.go b/server/app/goauto/task/image_search_link.go
new file mode 100644
index 0000000..a10ab59
--- /dev/null
+++ b/server/app/goauto/task/image_search_link.go
@@ -0,0 +1,50 @@
+package task
+
+import (
+	"context"
+	"errors"
+	"strings"
+
+	"go-admin/app/goauto/models"
+	"gorm.io/gorm"
+)
+
+// autoLinkImageSearch is deliberately a narrow post-result hook. It only
+// writes an association when the task was a complete collection, the frozen
+// original association is unchanged, and the target product is active. Manual
+// changes made while the Agent was running win by the CAS predicate.
+func (service *Service) autoLinkImageSearch(ctx context.Context, taskID uint64) error {
+	var task models.CollectionTask
+	if err := service.DB.WithContext(ctx).First(&task, taskID).Error; err != nil {
+		return internalError(err)
+	}
+	if task.Source != models.CollectionTaskSourceImageSearch || task.Status != models.TaskStatusCompleted || task.PDDProductID == nil || task.ImageSearchSnapshot == nil {
+		return nil
+	}
+	snapshot, err := loadImageSearchSnapshot(task)
+	if err != nil {
+		return err
+	}
+	if snapshot.PriceGuardSkipped {
+		return nil
+	}
+	var product models.ShopeeProduct
+	if err := service.DB.WithContext(ctx).First(&product, snapshot.ShopeeProductID).Error; err != nil {
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil
+		}
+		return internalError(err)
+	}
+	// PDD products are RMB in the current contract; unlike-currency snapshots
+	// must remain available for manual review and can never auto-link.
+	if strings.ToUpper(strings.TrimSpace(product.Currency)) != "CNY" {
+		return nil
+	}
+	result := service.DB.WithContext(ctx).Model(&models.ShopeeProduct{}).
+		Where("id = ? AND pdd_product_id IS NULL AND image_search_linked = ?", product.ID, false).
+		Updates(map[string]any{"pdd_product_id": *task.PDDProductID, "image_search_linked": true})
+	if result.Error != nil {
+		return internalError(result.Error)
+	}
+	return nil
+}
diff --git a/server/app/goauto/task/result_service.go b/server/app/goauto/task/result_service.go
index 57d8779..8fdd34e 100644
--- a/server/app/goauto/task/result_service.go
+++ b/server/app/goauto/task/result_service.go
@@ -123,6 +123,9 @@ func (service *Service) SubmitResult(ctx context.Context, taskID uint64, request
 	if err := service.activatePersistedReplacement(ctx, taskID); err != nil {
 		return DetailResponse{}, err
 	}
+	if err := service.autoLinkImageSearch(ctx, taskID); err != nil {
+		return DetailResponse{}, err
+	}
 	detail, err := service.Detail(ctx, taskID)
 	detail.Replayed = replayed
 	return detail, err