A thin film transistor array substrate comprises: a substrate, a plurality of thin film transistors disposed on the substrate, wherein each of the plurality of thin film transistors comprises: a gate electrode structure, an isolate protective layer disposed on the gate electrode structure, an active layer disposed on the isolate protective layer, a source electrode layer disposed on a side of the active layer and forming an ohmic contact with the active layer, a drain electrode layer disposed on other side of the active layer and forming an ohmic contact with the active layer, a first concentration doping layer disposed on the active layer and between the source electrode layer and the drain electrode layer, a passivation layer covered onto the active layer, the source electrode layer and the drain electrode layer, and a pixel electrode layer covered onto the passivation layer and the drain electrode layer.