diff --git a/Related-Projects.md b/Related-Projects.md
index e802fdb..6b95e73 100644
--- a/Related-Projects.md
+++ b/Related-Projects.md
@@ -21,6 +21,7 @@
 * [mruby-http](https://github.com/mattn/mruby-http) Binding for [http-parser](https://github.com/joyent/http-parser) by [mattn](https://github.com/mattn)
 * [mruby-httprequest](https://github.com/matsumoto-r/mruby-httprequest) simple http request using [mruby-http](https://github.com/mattn/mruby-http) by [matsumoto_r](https://github.com/matsumoto-r)
 * [mruby-iconv](https://github.com/mattn/mruby-iconv) libiconv interface by [mattn](https://github.com/mattn)
+* [mruby-io](https://github.com/mattn/mruby-io) IO, File implementation by [iij](https://github.com/iij)
 * [mruby-json](https://github.com/mattn/mruby-json) JSON encoder/decoder using [parson](https://github.com/kgabis/parson) by [mattn](https://github.com/mattn)
 * [mruby-md5](https://github.com/mattn/mruby-md5) MD5 digest function by [mattn](https://github.com/mattn)
 * [mruby-msagent](https://github.com/mattn/mruby-msagent) Microsoft Agent by [mattn](https://github.com/mattn)