diff --git a/README.md b/README.md
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 # py-graph
 [![Build Status](https://travis-ci.org/jajupmochi/py-graph.svg?branch=ljia)](https://travis-ci.org/jajupmochi/py-graph)
 [![codecov](https://codecov.io/gh/jajupmochi/py-graph/branch/ljia/graph/badge.svg)](https://codecov.io/gh/jajupmochi/py-graph)
+[![Documentation Status](https://readthedocs.org/projects/py-graph/badge/?version=ljia)](https://py-graph.readthedocs.io/en/ljia/?badge=ljia)
 
 A python package for graph kernels.