diff --git a/jjb/aaa.yaml b/jjb/aaa.yaml
index bdb3409..f7c9d5b 100644
--- a/jjb/aaa.yaml
+++ b/jjb/aaa.yaml
@@ -51,7 +51,8 @@
     scm:
       - git:
           url: '{gerrit-server-url}/aaa'
-          branches: '$GERRIT_BRANCH'
+          branches:
+            - '$GERRIT_BRANCH'
           refspec: '$GERRIT_RECSPEC'
           choosing-strategy: 'gerrit'
           do-not-fetch-tags: true