diff --git a/cmd/agent/main.go b/cmd/agent/main.go
index e505bdea6..801da119f 100644
--- a/cmd/agent/main.go
+++ b/cmd/agent/main.go
@@ -77,7 +77,7 @@ type GrpcProxyAgentOptions struct {
 	serviceAccountTokenPath string
 }
 
-func (o *GrpcProxyAgentOptions) ClientSetConfig(dialOption grpc.DialOption) *agent.ClientSetConfig {
+func (o *GrpcProxyAgentOptions) ClientSetConfig(dialOption ...grpc.DialOption) *agent.ClientSetConfig {
 	return &agent.ClientSetConfig{
 		Address:                 fmt.Sprintf("%s:%d", o.proxyServerHost, o.proxyServerPort),
 		AgentID:                 o.agentID,
diff --git a/pkg/agent/clientset.go b/pkg/agent/clientset.go
index f64a6bfbc..f0292ad71 100644
--- a/pkg/agent/clientset.go
+++ b/pkg/agent/clientset.go
@@ -43,7 +43,7 @@ type ClientSet struct {
 	// proxy server.
 	probeInterval time.Duration // The interval by which the agent
 	// periodically checks if its connections to the proxy server is ready.
-	dialOption grpc.DialOption
+	dialOption []grpc.DialOption
 	// file path contains service account token
 	serviceAccountTokenPath string
 	// channel to signal shutting down the client set. Primarily for test.
@@ -110,7 +110,7 @@ type ClientSetConfig struct {
 	AgentID                 string
 	SyncInterval            time.Duration
 	ProbeInterval           time.Duration
-	DialOption              grpc.DialOption
+	DialOption              []grpc.DialOption
 	ServiceAccountTokenPath string
 }
 
@@ -128,7 +128,7 @@ func (cc *ClientSetConfig) NewAgentClientSet(stopCh <-chan struct{}) *ClientSet
 }
 
 func (cs *ClientSet) newAgentClient() (*AgentClient, int, error) {
-	return newAgentClient(cs.address, cs.agentID, cs, cs.dialOption)
+	return newAgentClient(cs.address, cs.agentID, cs, cs.dialOption...)
 }
 
 func (cs *ClientSet) resetBackoff() *wait.Backoff {
diff --git a/tests/proxy_test.go b/tests/proxy_test.go
index 9017c0d44..9c49142ce 100644
--- a/tests/proxy_test.go
+++ b/tests/proxy_test.go
@@ -364,7 +364,7 @@ func runAgentWithID(agentID, addr string, stopCh <-chan struct{}) *agent.ClientS
 		AgentID:       agentID,
 		SyncInterval:  100 * time.Millisecond,
 		ProbeInterval: 100 * time.Millisecond,
-		DialOption:    grpc.WithInsecure(),
+		DialOption:    []grpc.DialOption{grpc.WithInsecure()},
 	}
 	client := cc.NewAgentClientSet(stopCh)
 	client.Serve()