diff --git a/doc/migrating_from_mailfull.md b/doc/migrating_from_mailfull.md
new file mode 100644
index 0000000..20234e6
--- /dev/null
+++ b/doc/migrating_from_mailfull.md
@@ -0,0 +1,24 @@
+Migrating from mailfull
+=======================
+
+Migrating from [directorz/mailfull](https://github.com/directorz/mailfull)
+
+Change directory to Mailfull directory.
+
+```
+# su - mailfull
+$ cd /home/mailfull
+```
+
+Initialize a directory as a Mailfull repository.
+
+```
+$ mailfull init
+```
+
+Delete unnecessary files.
+
+```
+$ rm -rf .git .gitignore bin docs lib README.md README.ja.md
+$ find domains -maxdepth 2 -name '.vforward' | xargs rm -f
+```