diff --git a/federation/ldap/src/main/java/org/keycloak/storage/ldap/mappers/membership/group/GroupLDAPStorageMapper.java b/federation/ldap/src/main/java/org/keycloak/storage/ldap/mappers/membership/group/GroupLDAPStorageMapper.java
index 700acd5f3a..f5f062082a 100644
--- a/federation/ldap/src/main/java/org/keycloak/storage/ldap/mappers/membership/group/GroupLDAPStorageMapper.java
+++ b/federation/ldap/src/main/java/org/keycloak/storage/ldap/mappers/membership/group/GroupLDAPStorageMapper.java
@@ -579,6 +579,11 @@ public class GroupLDAPStorageMapper extends AbstractLDAPStorageMapper implements
 
     @Override
     public List<UserModel> getGroupMembers(RealmModel realm, GroupModel kcGroup, int firstResult, int maxResults) {
+        if (config.getMode() == LDAPGroupMapperMode.IMPORT) {
+            // only results from Keycloak should be returned, or imported LDAP and KC items will duplicate
+            return Collections.emptyList();
+        }
+
         // TODO: with ranged search in AD we can improve the search using the specific range (not done for the moment)
         LDAPObject ldapGroup = loadLDAPGroupByName(kcGroup.getName());
         if (ldapGroup == null) {
diff --git a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/federation/ldap/LDAPGroupMapperTest.java b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/federation/ldap/LDAPGroupMapperTest.java
index cd34bf4dbe..4540eccfdb 100755
--- a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/federation/ldap/LDAPGroupMapperTest.java
+++ b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/federation/ldap/LDAPGroupMapperTest.java
@@ -417,6 +417,17 @@ public class LDAPGroupMapperTest extends AbstractLDAPTest {
             long dbGroupCount = rob.getGroupsCount();
             Assert.assertEquals(4, dbGroupCount);
 
+            // Check getGroupMembers
+            List<UserModel> group1Members = session.users().getGroupMembers(appRealm, group1, 0, 10);
+            List<UserModel> group11Members = session.users().getGroupMembers(appRealm, group11, 0, 10);
+            List<UserModel> group12Members = session.users().getGroupMembers(appRealm, group12, 0, 10);
+
+            Assert.assertEquals(0, group1Members.size());
+            Assert.assertEquals(1, group11Members.size());
+            Assert.assertEquals("robkeycloak", group11Members.get(0).getUsername());
+            Assert.assertEquals(1, group12Members.size());
+            Assert.assertEquals("robkeycloak", group12Members.get(0).getUsername());
+
             // Delete some group mappings in LDAP and check that it doesn't have any effect and user still has groups
             LDAPObject ldapGroup = groupMapper.loadLDAPGroupByName("group11");
             groupMapper.deleteGroupMappingInLDAP(robLdap, ldapGroup);
@@ -428,6 +439,17 @@ public class LDAPGroupMapperTest extends AbstractLDAPTest {
             Assert.assertTrue(robGroups.contains(group11));
             Assert.assertTrue(robGroups.contains(group12));
 
+            // Check getGroupMembers
+            group1Members = session.users().getGroupMembers(appRealm, group1, 0, 10);
+            group11Members = session.users().getGroupMembers(appRealm, group11, 0, 10);
+            group12Members = session.users().getGroupMembers(appRealm, group12, 0, 10);
+
+            Assert.assertEquals(0, group1Members.size());
+            Assert.assertEquals(1, group11Members.size());
+            Assert.assertEquals("robkeycloak", group11Members.get(0).getUsername());
+            Assert.assertEquals(1, group12Members.size());
+            Assert.assertEquals("robkeycloak", group12Members.get(0).getUsername());
+
             // Delete group mappings through model and verifies that user doesn't have them anymore
             rob.leaveGroup(group11);
             rob.leaveGroup(group12);