diff --git a/pkg/hostman/hostinfo/hostdhcp/dhcpserver.go b/pkg/hostman/hostinfo/hostdhcp/dhcpserver.go
index 28b960d3d4..6ce193719b 100644
--- a/pkg/hostman/hostinfo/hostdhcp/dhcpserver.go
+++ b/pkg/hostman/hostinfo/hostdhcp/dhcpserver.go
@@ -182,10 +182,12 @@ func (s *SGuestDHCPServer) getGuestConfig(
 	conf.ServerIP = net.ParseIP(v4Ip.NetAddr(int8(masklen)).String())
 	conf.SubnetMask = net.ParseIP(netutils2.Netlen2Mask(int(masklen)))
 	conf.BroadcastAddr = v4Ip.BroadcastAddr(int8(masklen)).ToBytes()
-	conf.Hostname = guestDesc.Name
 	if len(guestDesc.Hostname) > 0 {
 		conf.Hostname = guestDesc.Hostname
+	} else {
+		conf.Hostname = guestDesc.Name
 	}
+	conf.Hostname = strings.ToLower(conf.Hostname)
 	conf.Domain = nicdesc.Domain
 
 	// get main ip
diff --git a/pkg/util/dhcp/helpers.go b/pkg/util/dhcp/helpers.go
index 02324ebdcb..0cc38ca0df 100644
--- a/pkg/util/dhcp/helpers.go
+++ b/pkg/util/dhcp/helpers.go
@@ -59,11 +59,7 @@ type ResponseConfig struct {
 }
 
 func (conf ResponseConfig) GetHostname() string {
-	hostname := conf.Hostname
-	if conf.Domain != "" {
-		hostname = fmt.Sprintf("%s.%s", hostname, conf.Domain)
-	}
-	return hostname
+	return conf.Hostname
 }
 
 func GetOptUint16(val uint16) []byte {