diff --git a/pkg/apis/v1alpha/iam/iam_handler.go b/pkg/apis/v1alpha/iam/iam_handler.go
index 2705c1d37..6063fe159 100644
--- a/pkg/apis/v1alpha/iam/iam_handler.go
+++ b/pkg/apis/v1alpha/iam/iam_handler.go
@@ -25,6 +25,7 @@ import (
 	"strings"
 	"kubesphere.io/kubesphere/pkg/constants"
 	"k8s.io/api/rbac/v1"
+	"k8s.io/kubernetes/pkg/util/slice"
 )
 
 func Register(ws *restful.WebService) {
@@ -86,7 +87,9 @@ func roleUsersHandler(req *restful.Request, resp *restful.Response) {
 
 	for _, roleBinding := range roleBindings {
 		for _, subject := range roleBinding.Subjects {
-			if subject.Kind == v1.UserKind {
+			if subject.Kind == v1.UserKind &&
+				!strings.HasPrefix(subject.Name, "system") &&
+				!slice.ContainsString(users, subject.Name, nil) {
 				users = append(users, subject.Name)
 			}
 		}
@@ -110,7 +113,8 @@ func clusterRoleUsersHandler(req *restful.Request, resp *restful.Response) {
 
 	for _, roleBinding := range roleBindings {
 		for _, subject := range roleBinding.Subjects {
-			if subject.Kind == v1.UserKind && !strings.HasPrefix(subject.Name, "system") {
+			if subject.Kind == v1.UserKind && !strings.HasPrefix(subject.Name, "system") &&
+				!slice.ContainsString(users, subject.Name, nil) {
 				users = append(users, subject.Name)
 			}
 		}