pdf.setFont("helvetica");
pdf.setFontType("bold");
pdf.setFontSize(9);

表上的pdf.fromHTML似乎忽略了样式，甚至忽略了jsPdf设置，如pdf.setFont("helvetica");等。
以便您可以对原始jspdf.debug.js文件进行更改：
a）默认autoSize为false，因此您可以更改它。
B）默认fontSize为12 -您应该发送d个较小的值（将您的值添加到最后一个参数）。

/*** TABLE RENDERING ***/
} else if (cn.nodeName === "TABLE") {
    table2json = tableToJson(cn, renderer);
    renderer.y += 10;
    renderer.pdf.table(renderer.x, renderer.y, table2json.rows, table2json.headers, {
            autoSize : true,
            printHeaders : true,
            margins : renderer.pdf.margins_doc,
            fontSize : 9
    });
}

我给予一个对我有用的例子：

function imprimirPdf() {
    var pdf = new jsPDF('p', 'pt', 'letter');
    pdf.setFont("arial", "bold");
    pdf.setFontSize(14);
    pdf.text(20, 20, 'Consulta');
    $("#idTablaDatos").css("font-size", "10px");// change property value
    $("#idTablaDetalle").css("font-size", "10px");// change property value
    source = $('#div_pdf').html();//div_pdf contains idTablaDatos and idTablaDetalle
    $("#idTablaDatos").css("font-size","14px");// original value
    $("#idTablaDetalle").css("font-size","14px");// original value

    specialElementHandlers = {
        '#bypassme': function (element, renderer) {
            return true
        }
    };
    margins = {
        top: 80,
        bottom: 60,
        left: 40,
        width: 522
    };
    // all coords and widths are in jsPDF instance's declared units
    // 'inches' in this case

    pdf.fromHTML(
            source, // HTML string or DOM elem ref.
            margins.left, // x coord
            margins.top, {// y coord
                'width': margins.width, // max width of content on PDF
                'elementHandlers': specialElementHandlers
            },
    function (dispose) {
        // dispose: object with X, Y of the last line add to the PDF 
        //          this allow the insertion of new lines after html
        pdf.save('Test.pdf');
    }, margins);

}

这对我很有效：

table.style.fontSize = '5px';

试用AutoTable-jsPDF的表格插件

<a class="pull-right btn btn-warning btn-large" href="#" onclick="generate();"><i class="fa fa-file-excel-o"></i> PDF Data</a>
<table class="table table-bordered table-striped" id="basic-table">

<script src='https://cdn.rawgit.com/simonbengtsson/jsPDF/requirejs-fix-dist/dist/jspdf.debug.js'></script>
<script src='https://unpkg.com/jspdf-autotable@2.3.2'></script>
<script src="<?php echo base_url();?>assets/bower_components/jspdf/dist/index.js"></script>
<script>

function generate() {

  var doc = new jsPDF('l', 'pt', 'a4');
  doc.setFontSize(12);

  var res = doc.autoTableHtmlToJson(document.getElementById("basic-table"));
  doc.autoTable(res.columns, res.data, {margin: {top: 80}});

  var header = function(data) {
    doc.setFontSize(18);
    doc.setTextColor(40);
    doc.setFontStyle('normal');
    //doc.addImage(headerImgData, 'JPEG', data.settings.margin.left, 20, 50, 50);
    doc.text("Country List", data.settings.margin.left, 50);
  };

  var options = {
    beforePageContent: header,
    margin: {
      top: 80
    },

    startY: doc.autoTableEndPosY() + 20
  };

  doc.autoTable(res.columns, res.data, options);

  doc.save("Test.pdf");
}


</script>

简单直接：

var doc = new jspdf.jsPDF();
doc.autoTable({ html: '#tabelaDadosExtrato' });
doc.save('extrato-cliente-bet.pdf');

基于https://github.com/simonbengtsson/jsPDF-AutoTable中的示例