diff --git a/ci/travis/determine_tests_to_run.py b/ci/travis/determine_tests_to_run.py
index 8b040154a..0b2957a48 100644
--- a/ci/travis/determine_tests_to_run.py
+++ b/ci/travis/determine_tests_to_run.py
@@ -88,6 +88,7 @@ if __name__ == "__main__":
                 RAY_CI_LINUX_WHEELS_AFFECTED = 1
                 RAY_CI_MACOS_WHEELS_AFFECTED = 1
             elif changed_file.startswith("python/ray/serve"):
+                RAY_CI_DOC_AFFECTED = 1
                 RAY_CI_SERVE_AFFECTED = 1
                 RAY_CI_LINUX_WHEELS_AFFECTED = 1
                 RAY_CI_MACOS_WHEELS_AFFECTED = 1