diff --git a/ddl/worker.go b/ddl/worker.go
index 5179c7278c..47214a5ee7 100644
--- a/ddl/worker.go
+++ b/ddl/worker.go
@@ -95,10 +95,10 @@ func asyncNotify(ch chan struct{}) {
 	}
 }
 
-func (d *ddl) verifyOwner(t *meta.TMeta) (bool, error) {
+func (d *ddl) verifyOwner(t *meta.TMeta) error {
 	owner, err := t.GetDDLOwner()
 	if err != nil {
-		return false, errors.Trace(err)
+		return errors.Trace(err)
 	}
 
 	if owner == nil {
@@ -117,14 +117,20 @@ func (d *ddl) verifyOwner(t *meta.TMeta) (bool, error) {
 		err = t.SetDDLOwner(owner)
 	}
 
-	return owner.OwnerID == d.uuid, errors.Trace(err)
+	if err != nil {
+		return errors.Trace(err)
+	} else if owner.OwnerID != d.uuid {
+		return errors.Trace(ErrNotOwner)
+	}
+
+	return nil
 }
 
 // every time we enter another state, we must call this function.
 func (d *ddl) updateJob(t *meta.TMeta, j *model.Job) error {
-	isOwner, err := d.verifyOwner(t)
-	if !isOwner {
-		return errors.Errorf("not owner, can't update job")
+	err := d.verifyOwner(t)
+	if err != nil {
+		return errors.Trace(err)
 	}
 
 	err = t.UpdateDDLJob(0, j)
@@ -154,9 +160,9 @@ func (d *ddl) getFirstJob() (*model.Job, error) {
 func (d *ddl) finishJob(job *model.Job) error {
 	// done, notice and run next job.
 	err := d.meta.RunInNewTxn(false, func(t *meta.TMeta) error {
-		isOwner, err := d.verifyOwner(t)
-		if !isOwner {
-			return errors.Errorf("not owner, can't finish job")
+		err := d.verifyOwner(t)
+		if err != nil {
+			return errors.Trace(err)
 		}
 
 		_, err = t.DeQueueDDLJob()
@@ -172,26 +178,24 @@ func (d *ddl) finishJob(job *model.Job) error {
 	return errors.Trace(err)
 }
 
-func (d *ddl) checkOwner() (bool, error) {
-	var isOwner bool
+func (d *ddl) checkOwner() error {
 	err := d.meta.RunInNewTxn(false, func(t *meta.TMeta) error {
-		var err1 error
-		isOwner, err1 = d.verifyOwner(t)
-		return errors.Trace(err1)
+		return errors.Trace(d.verifyOwner(t))
 	})
 
-	return isOwner, errors.Trace(err)
+	return errors.Trace(err)
 }
 
+// ErrNotOwner means we are not owner and can't handle DDL jobs.
+var ErrNotOwner = errors.New("DDL: not owner")
+
 func (d *ddl) handleJobQueue() error {
 	for {
-		isOwner, err := d.checkOwner()
-
-		if err != nil || !isOwner {
-			// error or not owner
+		err := d.checkOwner()
+		if err != nil {
+			// error
 			return errors.Trace(err)
 		}
-
 		// become the owner
 		// get the first job and run
 		var job *model.Job