diff --git a/azure-pipelines-ci.yml b/azure-pipelines-ci.yml
index 31dd44e58c5..bcf48d66b22 100644
--- a/azure-pipelines-ci.yml
+++ b/azure-pipelines-ci.yml
@@ -1,4 +1,4 @@
-trigger:
+pr:
   - master
 
 # The `resources` specify the location and version of the 1ES PT.