//行合併外掛
jQuery.fn.rowspan = function(colIdx) { //封裝的一個JQuery小外掛
    return this.each(function(){
        var that;
        $('tr', this).each(function(row) {
            $('td:eq('+colIdx+')', this).each(function(col) {
                if (that!=null && this.innerText == that.outerText) {
                    rowspan = $(that).attr("rowSpan");
                    if (rowspan == undefined) {
                        $(that).attr("rowSpan",1);
                        rowspan = $(that).attr("rowSpan");
                    }
                    rowspan = Number(rowspan)+1;
                    $(that).attr("rowSpan",rowspan);
                    $(that).css("line-height", 50 * rowspan + 'px');
                    $(this).hide();
                } else {
                    that = this;
                }
            });
        });
    });
}

$("#dwgsTable").rowspan(0);

dwgsTable：table的ID

<table class="table table-bordered table-condensed" id="dwgsTable">
    <thead>
    <tr>
        <th style="width: 45px">序號</th>
        <th>專案名稱</th>
        <th>單位工程名稱</th>
        <th>專業</th>
        <th>送審金額</th>
        <th>協審人員</th>
        <th>協審複核人員</th>
    </tr>

</thead>

</table>