<span class="help-block" style="list-style-type: none;"> @Html.ValidationSummary() </span>
<span class="help-block"> @Html.ValidationSummary() </span>
您可以在ValidationSummary生成的ul元素上将CSS属性list-style-type设置为none.试试这个：
.help-block ul { list-style-type: none; }
