diff --git a/src/wp-includes/class-wp-user-query.php b/src/wp-includes/class-wp-user-query.php
index 4f56ca940e..5bb115fdfd 100644
--- a/src/wp-includes/class-wp-user-query.php
+++ b/src/wp-includes/class-wp-user-query.php
@@ -1013,7 +1013,7 @@ class WP_User_Query {
 			$_orderby          = 'post_count';
 		} elseif ( 'ID' === $orderby || 'id' === $orderby ) {
 			$_orderby = 'ID';
-		} elseif ( 'meta_value' === $orderby || $this->get( 'meta_key' ) == $orderby ) {
+		} elseif ( 'meta_value' === $orderby || $this->get( 'meta_key' ) === $orderby ) {
 			$_orderby = "$wpdb->usermeta.meta_value";
 		} elseif ( 'meta_value_num' === $orderby ) {
 			$_orderby = "$wpdb->usermeta.meta_value+0";