diff --git a/framework/grid/DataColumn.php b/framework/grid/DataColumn.php
index e1402b2192..c1f51da510 100644
--- a/framework/grid/DataColumn.php
+++ b/framework/grid/DataColumn.php
@@ -91,7 +91,7 @@ class DataColumn extends Column
      */
     public $sortLinkOptions = [];
     /**
-     * @var string|array|boolean the HTML code representing a filter input (e.g. a text field, a dropdown list)
+     * @var string|array|null|false the HTML code representing a filter input (e.g. a text field, a dropdown list)
      * that is used for this data column. This property is effective only when [[GridView::filterModel]] is set.
      *
      * - If this property is not set, a text field will be generated as the filter input;