diff --git a/.drone.yml b/.drone.yml
index d7af546..563551b 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -34,6 +34,9 @@ steps:
         from_secret: DOCKER_USERNAME
       DOCKER_PASSWORD:
         from_secret: DOCKER_PASSWORD
+    when:
+      branch:
+        - master
 
 volumes:
   - name: book