diff --git a/README.md b/README.md
index 08c3f7f..c9bb63a 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,7 @@
 The common library mainly used by rk-entry.
 
 [![build](https://github.com/rookie-ninja/rk-common/actions/workflows/ci.yml/badge.svg)](https://github.com/rookie-ninja/rk-common/actions/workflows/ci.yml)
+[![codecov](https://codecov.io/gh/rookie-ninja/rk-common/branch/master/graph/badge.svg?token=7YYDHG1JVL)](https://codecov.io/gh/rookie-ninja/rk-common)
 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
 
 <!-- START doctoc generated TOC please keep comment here to allow auto update -->