diff --git a/library/think/Response.php b/library/think/Response.php
index 4f985948..aef1193d 100644
--- a/library/think/Response.php
+++ b/library/think/Response.php
@@ -43,7 +43,7 @@ class Response
             'text'   => 'text/plain',
         ];
 
-        if (!headers_sent() && isset($headers[$type])) {
+        if (!headers_sent() && !headers_list() && isset($headers[$type])) {
             header('Content-Type:' . $headers[$type] . '; charset=utf-8');
         }