A multi-channel thin film transistor structure including a first conducting layer, an insulating layer, a semiconductor layer and a second conducting layer is provided. The first conducting layer formed on a substrate includes a gate electrode. The insulating layer covers the first conducting layer. The semiconductor layer formed on the insulating layer includes a plurality of semiconductor islands located above the gate electrode. The second conducting layer formed on the insulating layer and on the semiconductor layer includes a source electrode and a drain electrode. Each one of the semiconductor islands is coupled electrically with the source electrode at one end and coupled electrically with the drain electrode at the other end.