diff --git a/tempest/api/identity/admin/v3/test_users.py b/tempest/api/identity/admin/v3/test_users.py
index 60abde7..e8d4a36 100644
--- a/tempest/api/identity/admin/v3/test_users.py
+++ b/tempest/api/identity/admin/v3/test_users.py
@@ -76,8 +76,8 @@
         self.addCleanup(self.client.delete_user, user['id'])
         # Update user with new password
         new_password = data_utils.rand_name('pass1')
-        self.client.update_user_password(user['id'], new_password,
-                                         original_password)
+        self.client.update_user_password(user['id'], password=new_password,
+                                         original_password=original_password)
         # TODO(lbragstad): Sleeping after the response status has been checked
         # and the body loaded as JSON allows requests to fail-fast. The sleep
         # is necessary because keystone will err on the side of security and
diff --git a/tempest/api/identity/v3/test_users.py b/tempest/api/identity/v3/test_users.py
index 2bab5d1..93814d3 100644
--- a/tempest/api/identity/v3/test_users.py
+++ b/tempest/api/identity/v3/test_users.py
@@ -50,13 +50,13 @@
         # to change password back. important for allow_tenant_isolation = false
         self.addCleanup(
             self.non_admin_client_for_cleanup.update_user_password,
-            user_id=user_id,
+            user_id,
             password=old_pass,
             original_password=new_pass)
 
         # user updates own password
         self.non_admin_client.update_user_password(
-            user_id=user_id, password=new_pass, original_password=old_pass)
+            user_id, password=new_pass, original_password=old_pass)
 
         # TODO(lbragstad): Sleeping after the response status has been checked
         # and the body loaded as JSON allows requests to fail-fast. The sleep
diff --git a/tempest/services/identity/v3/json/identity_client.py b/tempest/services/identity/v3/json/identity_client.py
index bbd8804..f1d8a35 100644
--- a/tempest/services/identity/v3/json/identity_client.py
+++ b/tempest/services/identity/v3/json/identity_client.py
@@ -81,13 +81,13 @@
         body = json.loads(body)
         return service_client.ResponseBody(resp, body)
 
-    def update_user_password(self, user_id, password, original_password):
-        """Updates a user password."""
-        update_user = {
-            'password': password,
-            'original_password': original_password
-        }
-        update_user = json.dumps({'user': update_user})
+    def update_user_password(self, user_id, **kwargs):
+        """Update a user password
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-identity-v3.html#changeUserPassword
+        """
+        update_user = json.dumps({'user': kwargs})
         resp, _ = self.post('users/%s/password' % user_id, update_user)
         self.expected_success(204, resp.status)
         return service_client.ResponseBody(resp)