diff --git a/application/command/Install.php b/application/command/Install.php
index f37e777..7b6caf6 100644
--- a/application/command/Install.php
+++ b/application/command/Install.php
@@ -48,7 +48,7 @@ class Install extends Command {
             exit;
         }
 
-        if (extension_loaded('redis')) {
+        if (!extension_loaded('redis')) {
             $output->highlight('缺少Redis扩展！');
             exit;
         }