diff --git a/dm/worker/server.go b/dm/worker/server.go
index ebf8213264..09280f6115 100644
--- a/dm/worker/server.go
+++ b/dm/worker/server.go
@@ -20,6 +20,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/siddontang/go-mysql/mysql"
 	"github.com/siddontang/go/sync2"
 	"github.com/soheilhy/cmux"
 	"go.uber.org/zap"
@@ -30,6 +31,7 @@ import (
 	"github.com/pingcap/dm/dm/pb"
 	"github.com/pingcap/dm/pkg/log"
 	"github.com/pingcap/dm/pkg/terror"
+	"github.com/pingcap/dm/pkg/utils"
 )
 
 var (
@@ -257,6 +259,8 @@ func (s *Server) QueryStatus(ctx context.Context, req *pb.QueryStatusRequest) (*
 		SourceID:      s.worker.cfg.SourceID,
 	}
 
+	unifyMasterBinlogPos(resp, s.worker.cfg.EnableGTID)
+
 	if len(resp.SubTaskStatus) == 0 {
 		resp.Msg = "no sub task started"
 	}
@@ -464,3 +468,73 @@ func (s *Server) splitHostPort() (host, port string, err error) {
 	}
 	return
 }
+
+// unifyMasterBinlogPos eliminates different masterBinlog in one response
+// see https://github.com/pingcap/dm/issues/727
+func unifyMasterBinlogPos(resp *pb.QueryStatusResponse, enableGTID bool) {
+	var (
+		syncStatus          []*pb.SubTaskStatus_Sync
+		syncMasterBinlog    []*mysql.Position
+		lastestMasterBinlog mysql.Position // not pointer, to make use of zero value and avoid nil check
+		relayMasterBinlog   *mysql.Position
+	)
+
+	// uninitialized mysql.Position is less than any initialized mysql.Position
+	if resp.RelayStatus.Stage != pb.Stage_Stopped {
+		var err error
+		relayMasterBinlog, err = utils.DecodeBinlogPosition(resp.RelayStatus.MasterBinlog)
+		if err != nil {
+			log.L().Error("failed to decode relay's master binlog position", zap.Stringer("response", resp), zap.Error(err))
+			return
+		}
+		lastestMasterBinlog = *relayMasterBinlog
+	}
+
+	for _, stStatus := range resp.SubTaskStatus {
+		if stStatus.Unit == pb.UnitType_Sync {
+			s := stStatus.Status.(*pb.SubTaskStatus_Sync)
+			syncStatus = append(syncStatus, s)
+
+			position, err := utils.DecodeBinlogPosition(s.Sync.MasterBinlog)
+			if err != nil {
+				log.L().Error("failed to decode sync's master binlog position", zap.Stringer("response", resp), zap.Error(err))
+				return
+			}
+			if lastestMasterBinlog.Compare(*position) < 0 {
+				lastestMasterBinlog = *position
+			}
+			syncMasterBinlog = append(syncMasterBinlog, position)
+		}
+	}
+
+	// re-check relay
+	if resp.RelayStatus.Stage != pb.Stage_Stopped && lastestMasterBinlog.Compare(*relayMasterBinlog) != 0 {
+		resp.RelayStatus.MasterBinlog = lastestMasterBinlog.String()
+
+		// if enableGTID, modify output binlog position doesn't affect RelayCatchUpMaster, skip check
+		if !enableGTID {
+			relayPos, err := utils.DecodeBinlogPosition(resp.RelayStatus.RelayBinlog)
+			if err != nil {
+				log.L().Error("failed to decode relay binlog position", zap.Stringer("response", resp), zap.Error(err))
+				return
+			}
+			catchUp := lastestMasterBinlog.Compare(*relayPos) == 0
+
+			resp.RelayStatus.RelayCatchUpMaster = catchUp
+		}
+	}
+	// re-check syncer
+	for i, sStatus := range syncStatus {
+		if lastestMasterBinlog.Compare(*syncMasterBinlog[i]) != 0 {
+			syncerPos, err := utils.DecodeBinlogPosition(sStatus.Sync.SyncerBinlog)
+			if err != nil {
+				log.L().Error("failed to decode syncer binlog position", zap.Stringer("response", resp), zap.Error(err))
+				return
+			}
+			synced := lastestMasterBinlog.Compare(*syncerPos) == 0
+
+			sStatus.Sync.MasterBinlog = lastestMasterBinlog.String()
+			sStatus.Sync.Synced = synced
+		}
+	}
+}
diff --git a/dm/worker/server_test.go b/dm/worker/server_test.go
index ab4c0fcdb5..1847d084a2 100644
--- a/dm/worker/server_test.go
+++ b/dm/worker/server_test.go
@@ -202,3 +202,108 @@ func (t *testServer) TestQueryError(c *C) {
 	c.Assert(resp.SubTaskError, HasLen, 1)
 	c.Assert(resp.SubTaskError[0].String(), Matches, `[\s\S]*mockSubtaskFail[\s\S]*`)
 }
+
+func (t *testServer) TestUnifyMasterBinlogPos(c *C) {
+	var (
+		pos1 = "(bin.000001, 3134)"
+		pos2 = "(bin.000001, 3234)"
+		pos3 = "(bin.000001, 3334)"
+		pos4 = "(bin.000001, 3434)"
+	)
+
+	// 1. should modify nothing
+	resp := &pb.QueryStatusResponse{
+		SubTaskStatus: []*pb.SubTaskStatus{{
+			Name:   "test",
+			Status: &pb.SubTaskStatus_Msg{Msg: "sub task not started"},
+		}},
+		RelayStatus: &pb.RelayStatus{
+			Stage: pb.Stage_Stopped,
+		},
+	}
+	resp2 := &pb.QueryStatusResponse{
+		SubTaskStatus: []*pb.SubTaskStatus{{
+			Name:   "test",
+			Status: &pb.SubTaskStatus_Msg{Msg: "sub task not started"},
+		}},
+		RelayStatus: &pb.RelayStatus{
+			MasterBinlog: pos1, RelayBinlog: pos1, RelayCatchUpMaster: true,
+		},
+	}
+	resp3 := &pb.QueryStatusResponse{
+		SubTaskStatus: []*pb.SubTaskStatus{{
+			Unit: pb.UnitType_Load,
+		}, {
+			Unit:   pb.UnitType_Sync,
+			Status: &pb.SubTaskStatus_Sync{Sync: &pb.SyncStatus{MasterBinlog: pos2, SyncerBinlog: pos2, Synced: true}},
+		}},
+		RelayStatus: &pb.RelayStatus{
+			Stage: pb.Stage_Stopped,
+		},
+	}
+
+	for _, r := range []*pb.QueryStatusResponse{resp, resp2, resp3} {
+		// clone resp
+		bytes, _ := r.Marshal()
+		originReps := &pb.QueryStatusResponse{}
+		err := originReps.Unmarshal(bytes)
+		c.Assert(err, IsNil)
+
+		unifyMasterBinlogPos(r, false)
+		c.Assert(r, DeepEquals, originReps)
+	}
+
+	// 2. could work on multiple status
+	resp = &pb.QueryStatusResponse{
+		SubTaskStatus: []*pb.SubTaskStatus{{
+			Unit: pb.UnitType_Load,
+		}, {
+			Unit:   pb.UnitType_Sync,
+			Status: &pb.SubTaskStatus_Sync{Sync: &pb.SyncStatus{MasterBinlog: pos2, SyncerBinlog: pos2, Synced: true}},
+		}, {
+			Unit:   pb.UnitType_Sync,
+			Status: &pb.SubTaskStatus_Sync{Sync: &pb.SyncStatus{MasterBinlog: pos4, SyncerBinlog: pos3, Synced: false}},
+		}},
+		RelayStatus: &pb.RelayStatus{
+			MasterBinlog: pos1, RelayBinlog: pos1, RelayCatchUpMaster: true,
+		},
+	}
+	unifyMasterBinlogPos(resp, false)
+
+	sync1 := resp.SubTaskStatus[1].Status.(*pb.SubTaskStatus_Sync).Sync
+	c.Assert(sync1.MasterBinlog, Equals, pos4)
+	c.Assert(sync1.Synced, IsFalse)
+	sync2 := resp.SubTaskStatus[2].Status.(*pb.SubTaskStatus_Sync).Sync
+	c.Assert(sync2.MasterBinlog, Equals, pos4)
+	c.Assert(sync2.Synced, IsFalse)
+	relay := resp.RelayStatus
+	c.Assert(relay.MasterBinlog, Equals, pos4)
+	c.Assert(relay.RelayCatchUpMaster, IsFalse)
+
+	// 3. test unifyMasterBinlogPos(..., enableGTID = true)
+	resp = &pb.QueryStatusResponse{
+		SubTaskStatus: []*pb.SubTaskStatus{{
+			Unit: pb.UnitType_Load,
+		}, {
+			Unit:   pb.UnitType_Sync,
+			Status: &pb.SubTaskStatus_Sync{Sync: &pb.SyncStatus{MasterBinlog: pos2, SyncerBinlog: pos2, Synced: true}},
+		}, {
+			Unit:   pb.UnitType_Sync,
+			Status: &pb.SubTaskStatus_Sync{Sync: &pb.SyncStatus{MasterBinlog: pos4, SyncerBinlog: pos3, Synced: false}},
+		}},
+		RelayStatus: &pb.RelayStatus{
+			MasterBinlog: pos1, RelayBinlog: pos1, RelayCatchUpMaster: true,
+		},
+	}
+	unifyMasterBinlogPos(resp, true)
+
+	sync1 = resp.SubTaskStatus[1].Status.(*pb.SubTaskStatus_Sync).Sync
+	c.Assert(sync1.MasterBinlog, Equals, pos4)
+	c.Assert(sync1.Synced, IsFalse)
+	sync2 = resp.SubTaskStatus[2].Status.(*pb.SubTaskStatus_Sync).Sync
+	c.Assert(sync2.MasterBinlog, Equals, pos4)
+	c.Assert(sync2.Synced, IsFalse)
+	relay = resp.RelayStatus
+	c.Assert(relay.MasterBinlog, Equals, pos4)
+	c.Assert(relay.RelayCatchUpMaster, IsTrue)
+}