diff --git a/config.php b/config.php
index c79846f..cbf0b4c 100644
--- a/config.php
+++ b/config.php
@@ -4,8 +4,8 @@ const MTEE_CLASS_DIR        = __DIR__ . '/class/';
 const MTEE_TEMPLATE_DIR     = __DIR__ . '/template/';
 const MTEE_NAME_KEYWORDS    = 'mtee_meta_keywords';
 const MTEE_NAME_DESCRIPTION = 'mtee_meta_description';
-const MTEE_NAME_NOINDEX      = 'mtee_robots_noindex';
-const MTEE_NAME_NOFOLLOW    = 'mtee_robots_nofollow';
+const MTEE_NAME_NOINDEX      = '_mtee_robots_noindex';
+const MTEE_NAME_NOFOLLOW    = '_mtee_robots_nofollow';
 
 const MTEE_META_DESC_TOP_BASE        = 'トップページです';
 const MTEE_META_DESC_SINGLE_BASE     = 'ページです。';
diff --git a/uninstall.php b/uninstall.php
index c6e46c3..31b51d4 100644
--- a/uninstall.php
+++ b/uninstall.php
@@ -12,8 +12,8 @@ delete_option( '_mtee' );
 $delete_post_meta_keys = array(
 	'mtee_meta_keywords',
 	'mtee_meta_description',
-	'mtee_robots_noindex',
-	'mtee_robots_nofollow',
+	'_mtee_robots_noindex',
+	'_mtee_robots_nofollow',
 );
 foreach ( $delete_post_meta_keys as $delete_post_meta_key ) {
 	delete_post_meta_by_key( $delete_post_meta_key );