diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index b878f37a5b8e807e5aa346e0074a741f2f8b6cc5..1304d6fe196c11a14a012b9f236b7a6682522e05 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -128,7 +128,7 @@ Please install pre-commit, which automatically reformat the changes to C/C++ and
 
 Please remember to add related unit tests.
 
-- For C/C++ code, please follow [`google-test` Primer](https://github.com/google/googletest/blob/master/googletest/docs/Primer.md).
+- For C/C++ code, please follow [`google-test` Primer](https://github.com/google/googletest/blob/master/googletest/docs/primer.md) .
 
 - For Python code, please use [Python's standard `unittest` package](http://pythontesting.net/framework/unittest/unittest-introduction/).