diff --git a/config/config_loader.go b/config/config_loader.go
index 99c35b22f1..9fbe8f91aa 100644
--- a/config/config_loader.go
+++ b/config/config_loader.go
@@ -77,7 +77,7 @@ func registerServiceInstance() {
 	if err != nil {
 		panic(err)
 	}
-	p := extension.GetProtocol(constant.RegistryKey)
+	p := extension.GetProtocol(constant.RegistryProtocol)
 	var rp registry.RegistryFactory
 	var ok bool
 	if rp, ok = p.(registry.RegistryFactory); !ok {
diff --git a/config/graceful_shutdown.go b/config/graceful_shutdown.go
index 54ed81b601..de3254183f 100644
--- a/config/graceful_shutdown.go
+++ b/config/graceful_shutdown.go
@@ -119,7 +119,7 @@ func BeforeShutdown() {
 
 func destroyAllRegistries() {
 	logger.Info("Graceful shutdown --- Destroy all registriesConfig. ")
-	registryProtocol := extension.GetProtocol(constant.RegistryKey)
+	registryProtocol := extension.GetProtocol(constant.RegistryProtocol)
 	registryProtocol.Destroy()
 }
 
diff --git a/config/service_config.go b/config/service_config.go
index fe8ba4b97a..d669c8c5c3 100644
--- a/config/service_config.go
+++ b/config/service_config.go
@@ -294,7 +294,7 @@ func (s *ServiceConfig) Export() error {
 			s.cacheMutex.Lock()
 			if s.cacheProtocol == nil {
 				logger.Debugf(fmt.Sprintf("First load the registry protocol, url is {%v}!", ivkURL))
-				s.cacheProtocol = extension.GetProtocol("registry")
+				s.cacheProtocol = extension.GetProtocol(constant.RegistryProtocol)
 			}
 			s.cacheMutex.Unlock()
 
diff --git a/registry/protocol/protocol.go b/registry/protocol/protocol.go
index 1b0d390d09..a869ab716f 100644
--- a/registry/protocol/protocol.go
+++ b/registry/protocol/protocol.go
@@ -70,7 +70,7 @@ type registryProtocol struct {
 }
 
 func init() {
-	extension.SetProtocol("registry", GetProtocol)
+	extension.SetProtocol(constant.RegistryProtocol, GetProtocol)
 }
 
 func newRegistryProtocol() *registryProtocol {