diff --git a/internal/querynodev2/cluster/worker.go b/internal/querynodev2/cluster/worker.go
index af2bc7a215e96..9261dac91089d 100644
--- a/internal/querynodev2/cluster/worker.go
+++ b/internal/querynodev2/cluster/worker.go
@@ -107,17 +107,13 @@ func (w *remoteWorker) Delete(ctx context.Context, req *querypb.DeleteRequest) e
 		zap.Int64("workerID", req.GetBase().GetTargetID()),
 	)
 	status, err := w.client.Delete(ctx, req)
-	if err != nil {
-		log.Warn("failed to call Delete via grpc worker",
-			zap.Error(err),
-		)
+	if err := merr.CheckRPCCall(status, err); err != nil {
+		if funcutil.IsGrpcErr(err, codes.Unimplemented) {
+			log.Warn("invoke legacy querynode Delete method, ignore error", zap.Error(err))
+			return nil
+		}
+		log.Warn("failed to call Delete, worker return error", zap.Error(err))
 		return err
-	} else if status.GetErrorCode() != commonpb.ErrorCode_Success {
-		log.Warn("failed to call Delete, worker return error",
-			zap.String("errorCode", status.GetErrorCode().String()),
-			zap.String("reason", status.GetReason()),
-		)
-		return merr.Error(status)
 	}
 	return nil
 }
diff --git a/internal/querynodev2/cluster/worker_test.go b/internal/querynodev2/cluster/worker_test.go
index 358ec2b5af5ab..55c0e97f1cf48 100644
--- a/internal/querynodev2/cluster/worker_test.go
+++ b/internal/querynodev2/cluster/worker_test.go
@@ -178,6 +178,19 @@ func (s *RemoteWorkerSuite) TestDelete() {
 
 		s.Error(err)
 	})
+
+	s.Run("legacy_querynode_unimplemented", func() {
+		defer func() { s.mockClient.ExpectedCalls = nil }()
+
+		s.mockClient.EXPECT().Delete(mock.Anything, mock.AnythingOfType("*querypb.DeleteRequest")).
+			Return(nil, status.Errorf(codes.Unimplemented, "mocked grpc unimplemented"))
+
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		err := s.worker.Delete(ctx, &querypb.DeleteRequest{})
+
+		s.NoError(err)
+	})
 }
 
 func (s *RemoteWorkerSuite) TestSearch() {