diff --git a/releasenotes/notes/use-keystone-v3-api-935860d30ddbb8e9.yaml b/releasenotes/notes/use-keystone-v3-api-935860d30ddbb8e9.yaml
new file mode 100644
index 0000000..dd6e924
--- /dev/null
+++ b/releasenotes/notes/use-keystone-v3-api-935860d30ddbb8e9.yaml
@@ -0,0 +1,5 @@
+---
+upgrade:
+  - Tempest now defaults to using Keystone v3 API for the
+    authentication, because Keystone v3 API is CURRENT and
+    the v2 API is deprecated.
diff --git a/tempest/config.py b/tempest/config.py
index 651c32e..7f45cf4 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -133,7 +133,7 @@
     cfg.StrOpt('uri_v3',
                help='Full URI of the OpenStack Identity API (Keystone), v3'),
     cfg.StrOpt('auth_version',
-               default='v2',
+               default='v3',
                help="Identity API version to be used for authentication "
                     "for API tests."),
     cfg.StrOpt('region',