diff --git a/internal/proxy/task.go b/internal/proxy/task.go
index 26090d5e59..287106df96 100644
--- a/internal/proxy/task.go
+++ b/internal/proxy/task.go
@@ -2283,43 +2283,43 @@ func (qt *queryTask) Execute(ctx context.Context) error {
 	return err
 }
 
-func copyQueryResultData(dst *milvuspb.QueryResults, src *internalpb.RetrieveResults) {
-	// handles initialization, cannot use idx==0 since first result may be empty
-	if len(dst.FieldsData) == 0 {
-		dst.FieldsData = append(dst.FieldsData, src.FieldsData...)
-	} else {
-		for i, fieldData := range src.FieldsData {
-			switch fieldType := fieldData.Field.(type) {
-			case *schemapb.FieldData_Scalars:
-				dstScalar := dst.FieldsData[i].GetScalars()
-				switch srcScalar := fieldType.Scalars.Data.(type) {
-				case *schemapb.ScalarField_BoolData:
-					dstScalar.GetBoolData().Data = append(dstScalar.GetBoolData().Data, srcScalar.BoolData.Data...)
-				case *schemapb.ScalarField_IntData:
-					dstScalar.GetIntData().Data = append(dstScalar.GetIntData().Data, srcScalar.IntData.Data...)
-				case *schemapb.ScalarField_LongData:
-					dstScalar.GetLongData().Data = append(dstScalar.GetLongData().Data, srcScalar.LongData.Data...)
-				case *schemapb.ScalarField_FloatData:
-					dstScalar.GetFloatData().Data = append(dstScalar.GetFloatData().Data, srcScalar.FloatData.Data...)
-				case *schemapb.ScalarField_DoubleData:
-					dstScalar.GetDoubleData().Data = append(dstScalar.GetDoubleData().Data, srcScalar.DoubleData.Data...)
-				default:
-					log.Debug("Query received not supported data type", zap.String("field type", fieldData.Type.String()))
-				}
-			case *schemapb.FieldData_Vectors:
-				dstVector := dst.FieldsData[i].GetVectors()
-				switch srcVector := fieldType.Vectors.Data.(type) {
-				case *schemapb.VectorField_BinaryVector:
-					dstVector.Data.(*schemapb.VectorField_BinaryVector).BinaryVector =
-						append(dstVector.Data.(*schemapb.VectorField_BinaryVector).BinaryVector, srcVector.BinaryVector...)
-				case *schemapb.VectorField_FloatVector:
-					dstVector.GetFloatVector().Data = append(dstVector.GetFloatVector().Data, srcVector.FloatVector.Data...)
-				default:
-					log.Debug("Query received not supported data type", zap.String("field type", fieldData.Type.String()))
-				}
+func mergeRetrieveResults(retrieveResults []*internalpb.RetrieveResults) (*milvuspb.QueryResults, error) {
+	var ret *milvuspb.QueryResults
+	var skipDupCnt int64 = 0
+	var idSet = make(map[int64]struct{})
+
+	// merge results and remove duplicates
+	for _, rr := range retrieveResults {
+		// skip empty result, it will break merge result
+		if rr == nil || rr.Ids == nil {
+			continue
+		}
+
+		if ret == nil {
+			ret = &milvuspb.QueryResults{
+				FieldsData: make([]*schemapb.FieldData, len(rr.FieldsData)),
+			}
+		}
+
+		if len(ret.FieldsData) != len(rr.FieldsData) {
+			return nil, fmt.Errorf("mismatch FieldData in RetrieveResults")
+		}
+
+		for i, id := range rr.Ids.GetIntId().GetData() {
+			if _, ok := idSet[id]; !ok {
+				typeutil.AppendFieldData(ret.FieldsData, rr.FieldsData, int64(i))
+				idSet[id] = struct{}{}
+			} else {
+				// primary keys duplicate
+				skipDupCnt++
 			}
 		}
 	}
+	if skipDupCnt > 0 {
+		log.Debug("skip duplicated query result", zap.Int64("count", skipDupCnt))
+	}
+
+	return ret, nil
 }
 
 func (qt *queryTask) PostExecute(ctx context.Context) error {
@@ -2354,31 +2354,21 @@ func (qt *queryTask) PostExecute(ctx context.Context) error {
 			return errors.New(reason)
 		}
 
-		qt.result = &milvuspb.QueryResults{
-			Status: &commonpb.Status{
+		var err error
+		qt.result, err = mergeRetrieveResults(filterRetrieveResults)
+		if err != nil {
+			return err
+		}
+
+		if len(qt.result.FieldsData) > 0 {
+			qt.result.Status = &commonpb.Status{
 				ErrorCode: commonpb.ErrorCode_Success,
-			},
-			FieldsData: make([]*schemapb.FieldData, 0),
-		}
-
-		validRetrieveResults := make([]*internalpb.RetrieveResults, 0)
-		for _, partialRetrieveResult := range filterRetrieveResults {
-			if partialRetrieveResult.Ids != nil {
-				validRetrieveResults = append(validRetrieveResults, partialRetrieveResult)
 			}
-		}
-
-		for _, partialRetrieveResult := range validRetrieveResults {
-			copyQueryResultData(qt.result, partialRetrieveResult)
-		}
-
-		if len(qt.result.FieldsData) == 0 {
+		} else {
 			log.Info("Query result is nil", zap.Any("requestID", qt.Base.MsgID), zap.Any("requestType", "query"))
-			qt.result = &milvuspb.QueryResults{
-				Status: &commonpb.Status{
-					ErrorCode: commonpb.ErrorCode_EmptyCollection,
-					Reason:    reason,
-				},
+			qt.result.Status = &commonpb.Status{
+				ErrorCode: commonpb.ErrorCode_EmptyCollection,
+				Reason:    reason,
 			}
 			return nil
 		}