diff --git a/README.md b/README.md
index f4b131b..47dfdab 100644
--- a/README.md
+++ b/README.md
@@ -123,6 +123,10 @@ By default peco starts in case insensitive mode. When this option is specified,
 
 Specifies the initial line position upon start up. E.g. If you want to start out with the second line selected, set it to "1" (because the index is 0 based)
 
+### --prompt
+
+Specifies the query line's prompt. It's `QUERY>` by default. And it's prior to configuration file's `Prompt`.
+
 Configuration File
 ==================