diff --git a/.github/workflows/cloud-tpu-ci-nightly.yml b/.github/workflows/cloud-tpu-ci-nightly.yml
index c925775d37c5..c70f87bc243a 100644
--- a/.github/workflows/cloud-tpu-ci-nightly.yml
+++ b/.github/workflows/cloud-tpu-ci-nightly.yml
@@ -4,6 +4,7 @@ on:
   schedule:
     - cron: "0 14 * * *"  # daily at 7am PST
   workflow_dispatch:  # allows triggering the workflow run manually
+  pull_request:
 
 jobs:
   cloud-tpu-test: