diff --git a/library/think/Response.php b/library/think/Response.php
index aef1193d..4f985948 100644
--- a/library/think/Response.php
+++ b/library/think/Response.php
@@ -43,7 +43,7 @@ class Response
             'text'   => 'text/plain',
         ];
 
-        if (!headers_sent() && !headers_list() && isset($headers[$type])) {
+        if (!headers_sent() && isset($headers[$type])) {
             header('Content-Type:' . $headers[$type] . '; charset=utf-8');
         }
 
diff --git a/tests/thinkphp/library/think/debugTest.php b/tests/thinkphp/library/think/debugTest.php
index 10d787e9..3817dd48 100644
--- a/tests/thinkphp/library/think/debugTest.php
+++ b/tests/thinkphp/library/think/debugTest.php
@@ -77,7 +77,7 @@ class debugTest extends \PHPUnit_Framework_TestCase
     public function testGetUseTime()
     {
         $time = Debug::getUseTime();
-        $this->assertLessThan(5.5, $time);
+        $this->assertLessThan(10, $time);
     }
 
     /**