ElementStacks

HTML

<script src="http://highcharts.com/js/testing.js"></script>
<script src="http://code.highcharts.com/highcharts.js"></script>
<script src="http://code.highcharts.com/modules/exporting.js"></script>
<div id="container" style="height: 300px"></div>
<button id="chageTitleBtn" type="button" onclick="changeTitle();">New Title</button>

JavaScript

var chart = new Highcharts.Chart({
    chart: {
        renderTo: 'container'
    },
    xAxis: {
        categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
    },
    title: {
        text: "Old Title"
    },
    series: [{
        data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4]        
    }]
});

$(document).ready(function(){
    $("#chageTitleBtn").click(function(){
        chart.setTitle({text: "New Title"});
    });
});