<script> $(function(){ var radio = $('#radio input[type="radio"]:checked').val(); $('#radio input[type="radio"]').on('click', function(){ if ($(this).val() == radio) { $(this).prop('checked', false); radio = false; } else { radio = $(this).val(); } }); }); </script> <div id="radio"> <input type="radio" name="item" value="1">アイテム1 <input type="radio" name="item" value="2">アイテム2 </div>
※要jquery