[Solved]-How to add image in Highcharts Title and subtitle-Highcharts

You need to set useHTML to true, and insert your image as HTML:

chart.setTitle({
    useHTML: true,
    text: "Testing" + " " + "<img src='../images/appendImage.png' alt='' />"
}, {
    text: "This is a test"
});

Working fiddle.