diff --git a/README.md b/README.md
index bda200d..cdce35f 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,9 @@ fluentd-ui is a browser-based [fluentd](http://www.fluentd.org) and [td-agent](h
 ## Requirements
 
 - ruby 2.1.3 or later (since v0.4.0)
+- fluentd v0.12
 
+Currently, fluentd-ui doesn't support fleuntd v1 and td-agent 3.
 And some additional packages (Debian / Ubuntu)
 
 - build-essential