pre_get_posts

Change ‘your-custom-post-type’ to your desired custom post type. You should use $query->is_main_query() to only show these in your archive page (if you don’t, your custom post type posts may show up in your sidebar widget, etc.). function hoge_show_cpt_archives( $query ) { if( is_tag() && $query->is_main_query() ) { $query->set( ‘post_type’, array( ‘post’, ‘your-custom-post-type’ )); return $query; } } add_filter( ‘pre_get_posts’, ‘hoge_show_cpt_archives’ );