diff --git a/replication/binlogsyncer.go b/replication/binlogsyncer.go
index ccbfb9f64..fa8a42d87 100644
--- a/replication/binlogsyncer.go
+++ b/replication/binlogsyncer.go
@@ -596,7 +596,7 @@ func (b *BinlogSyncer) writeRegisterSlaveCommand() error {
 	hostname := b.localHostname()
 
 	// This should be the name of slave host not the host we are connecting to.
-	data := make([]byte, 4+1+4+1+len(hostname)+1+len(b.cfg.User)+1+len(b.cfg.Password)+2+4+4)
+	data := make([]byte, 4+1+4+1+len(hostname)+1+len(b.cfg.User)+1+1+2+4+4)
 	pos := 4
 
 	data[pos] = COM_REGISTER_SLAVE
@@ -616,10 +616,8 @@ func (b *BinlogSyncer) writeRegisterSlaveCommand() error {
 	n = copy(data[pos:], b.cfg.User)
 	pos += n
 
-	data[pos] = uint8(len(b.cfg.Password))
+	data[pos] = uint8(0)
 	pos++
-	n = copy(data[pos:], b.cfg.Password)
-	pos += n
 
 	binary.LittleEndian.PutUint16(data[pos:], b.cfg.Port)
 	pos += 2