diff --git a/AWS-CLI-with-SeaweedFS.md b/AWS-CLI-with-SeaweedFS.md
index fe7c912..0af1b59 100644
--- a/AWS-CLI-with-SeaweedFS.md
+++ b/AWS-CLI-with-SeaweedFS.md
@@ -49,4 +49,20 @@ delete: s3://newbucket3/passwd
 $ aws --endpoint-url http://localhost:8333 s3 rb s3://newbucket3
 remove_bucket: newbucket3
 
+```
+
+
+# Presigned URL
+
+If [authentication](https://github.com/chrislusf/seaweedfs/wiki/Amazon-S3-API#authentication) is enabled, the url is usually not accessible without proper crendentials. But you can presign a url and access it.
+
+```
+
+# presign url, default to 1 hour
+$ aws --endpoint-url http://localhost:8333 s3 presign s3://newbucket/t.txt
+http://localhost:8333/newbucket/t.txt?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=some_access_key1%2F20200726%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20200726T161749Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=e0cc153209e414ca8168661f57827aa03ab84e7041ef9270ff639bcc519d24f5
+
+# access the url
+$ curl "http://localhost:8333/newbucket/t.txt?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=some_access_key1%2F20200726%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20200726T161749Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=e0cc153209e414ca8168661f57827aa03ab84e7041ef9270ff639bcc519d24f5"
+
 ```
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