Hey SUJAYS,
Please refer below sample.
HTML
<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.js"></script>
<script type="text/javascript">
$(function () {
$("#btnClear").click(function () {
$.each($('input[class="clear"]'), function () {
$(this).val("");
});
});
});
</script>
<asp:TextBox ID="TextBox1" runat="server" CssClass="clear" />
<asp:TextBox ID="TextBox2" runat="server" CssClass="clear" />
<asp:TextBox ID="TextBox3" runat="server" CssClass="clear" />
<asp:Button Text="Clear" runat="server" ID="btnClear" />
Screenshot