1), array('user_id' => 2) ); $a['Post3'] = array( array('user_name' => 1) ); function printValuesByKey($array, $key) { if (!is_array($array)) return; if (isset($array[$key])) echo $key .': '. $array[$key] .'
'; else foreach ($array as $v) printValuesByKey($v, $key); } printValuesByKey($a, 'user_id');