diff --git a/CHANGES.md b/CHANGES.md
index 31b051cb739..bd236472c33 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -26,5 +26,6 @@ Apollo 2.5.0
 * [Feature: Support ordinary users to modify personal information](https://github.com/apolloconfig/apollo/pull/5511)
 * [Feature: Support exporting and importing configurations for specified applications and clusters](https://github.com/apolloconfig/apollo/pull/5517)
 * [doc: Add rust apollo client link](https://github.com/apolloconfig/apollo/pull/5514)
+* [Perf: optimize namespace-related interface](https://github.com/apolloconfig/apollo/pull/5518)
 ------------------
 All issues and pull requests are [here](https://github.com/apolloconfig/apollo/milestone/16?closed=1)
diff --git a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceController.java b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceController.java
index 30846b73fd7..164f7961eec 100644
--- a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceController.java
+++ b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceController.java
@@ -101,6 +101,11 @@ public List<AppNamespace> findPublicAppNamespaces() {
     return appNamespaceService.findPublicAppNamespaces();
   }
 
+  @GetMapping("/appnamespaces/public/names")
+  public List<String> findPublicAppNamespaceNames() {
+    return appNamespaceService.findPublicAppNamespaceNames();
+  }
+
   @GetMapping("/apps/{appId}/envs/{env}/clusters/{clusterName}/namespaces")
   public List<NamespaceBO> findNamespaces(@PathVariable String appId, @PathVariable String env,
       @PathVariable String clusterName) {
diff --git a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/repository/AppNamespaceRepository.java b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/repository/AppNamespaceRepository.java
index 6edb245f114..79cf38d3396 100644
--- a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/repository/AppNamespaceRepository.java
+++ b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/repository/AppNamespaceRepository.java
@@ -32,6 +32,9 @@ public interface AppNamespaceRepository extends PagingAndSortingRepository<AppNa
 
   List<AppNamespace> findByIsPublicTrue();
 
+  @Query("SELECT a.name FROM AppNamespace a WHERE a.isPublic = true AND a.isDeleted = false")
+  List<String> findNamesByIsPublicTrue();
+
   List<AppNamespace> findByAppId(String appId);
 
   @Modifying
diff --git a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/AppNamespaceService.java b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/AppNamespaceService.java
index 4eb36b750d7..b2d120f8ec2 100644
--- a/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/AppNamespaceService.java
+++ b/apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/service/AppNamespaceService.java
@@ -70,6 +70,10 @@ public List<AppNamespace> findPublicAppNamespaces() {
     return appNamespaceRepository.findByIsPublicTrue();
   }
 
+  public List<String> findPublicAppNamespaceNames() {
+    return appNamespaceRepository.findNamesByIsPublicTrue();
+  }
+
   public AppNamespace findPublicAppNamespace(String namespaceName) {
     List<AppNamespace> appNamespaces =
         appNamespaceRepository.findByNameAndIsPublic(namespaceName, true);
diff --git a/apollo-portal/src/main/resources/static/scripts/controller/NamespaceController.js b/apollo-portal/src/main/resources/static/scripts/controller/NamespaceController.js
index be2f8165d8f..4d334246ea4 100644
--- a/apollo-portal/src/main/resources/static/scripts/controller/NamespaceController.js
+++ b/apollo-portal/src/main/resources/static/scripts/controller/NamespaceController.js
@@ -37,12 +37,12 @@ namespace_module.controller("LinkNamespaceController",
                 $scope.pageSetting = setting;
             });
 
-            NamespaceService.find_public_namespaces().then(function (result) {
+            NamespaceService.findPublicNamespaceNames().then(function (result) {
                 var publicNamespaces = [];
                 result.forEach(function (item) {
                     var namespace = {};
-                    namespace.id = item.name;
-                    namespace.text = item.name;
+                    namespace.id = item;
+                    namespace.text = item;
                     publicNamespaces.push(namespace);
                 });
                 $('#namespaces').select2({
diff --git a/apollo-portal/src/main/resources/static/scripts/services/NamespaceService.js b/apollo-portal/src/main/resources/static/scripts/services/NamespaceService.js
index 48d42f1d192..cefc057fa2e 100644
--- a/apollo-portal/src/main/resources/static/scripts/services/NamespaceService.js
+++ b/apollo-portal/src/main/resources/static/scripts/services/NamespaceService.js
@@ -61,6 +61,11 @@ appService.service("NamespaceService", ['$resource', '$q', 'AppUtil', function (
             method: 'GET',
             url: AppUtil.prefixPath() + '/apps/:appId/namespaces/:namespaceName/usage',
             isArray: true
+        },
+        findPublicNamespaceNames: {
+            method: 'GET',
+            isArray: true,
+            url: AppUtil.prefixPath() + '/appnamespaces/public/names'
         }
     });
 
@@ -211,6 +216,16 @@ appService.service("NamespaceService", ['$resource', '$q', 'AppUtil', function (
         return d.promise;
     }
 
+    function findPublicNamespaceNames() {
+        var d = $q.defer();
+        namespace_source.findPublicNamespaceNames({}, function (result) {
+            d.resolve(result);
+        }, function (result) {
+            d.reject(result);
+        });
+        return d.promise;
+    }
+
     return {
         find_public_namespaces: find_public_namespaces,
         createNamespace: createNamespace,
@@ -221,7 +236,8 @@ appService.service("NamespaceService", ['$resource', '$q', 'AppUtil', function (
         loadAppNamespace: loadAppNamespace,
         deleteAppNamespace: deleteAppNamespace,
         getLinkedNamespaceUsage: getLinkedNamespaceUsage,
-        getNamespaceUsage: getNamespaceUsage
+        getNamespaceUsage: getNamespaceUsage,
+        findPublicNamespaceNames: findPublicNamespaceNames
     }
 
 }]);