<!DOCTYPE html> <html> <head> <script language="javascript" src="https://code.jquery.com/jquery-3.1.1.min.js"></script> <style> </style> <script language="javascript"> $(document).ready(function(){ var str = $( "li.item-b" ).siblings(".item-d, .item-e"); str.css( "border", "1px solid pink" ); }); </script> </head> <body> <ul id="one" class="level-1"> <li class="item-i">I</li> <li id="ii" class="item-ii">II <ul class="level-2"> <li class="item-a">A</li> <li class="item-b">B <ul class="level-3"> <li class="item-1">1</li> <li class="item-2">2</li> <li class="item-3">3</li> </ul> </li> <li class="item-c">C</li> <li class="item-d">D</li> <li class="item-e">E</li> </ul> </li> <li class="item-iii">III</li> </ul> </body> </html>