diff --git a/Amazon-IAM-API.md b/Amazon-IAM-API.md
new file mode 100644
index 0000000..ed7e44c
--- /dev/null
+++ b/Amazon-IAM-API.md
@@ -0,0 +1,19 @@
+To be compatible with Amazon IAM API, a separate "weed iam" command is provided.
+
+# How it works?
+`weed iam` will start a stateless gateway server to bridge the Amazon IAM API to SeaweedFS Filer. For convenience, weed server -iam will start a master, a volume server, a filer, and the IAM gateway. And weed filer -iam can start a filer and the IAM gateway together also.
+
+# Supported APIs
+
+```
+* CreateAccessKey
+* CreateUser
+* CreatePolicy
+* CreateRole
+* PutUserPolicy
+* DeleteAccessKey
+* DeleteUser
+* GetUser
+* ListUsers
+* ListAccessKeys
+```
\ No newline at end of file