diff --git a/php/README.md b/php/README.md
index 16757be58b..b8cec1e3fd 100644
--- a/php/README.md
+++ b/php/README.md
@@ -16,7 +16,7 @@ generation functionality.
 
 To use PHP runtime library requires:
 
-- C extension: PHP 5.5, 5.6, or 7.
+- C extension: PHP 7
 - [PHP package](http://php.net/downloads.php): PHP 5.5, 5.6 or 7.
 
 ## Installation