A thin film transistor having Schottky barrier includes a substrate, a first gate conductive layer formed on the substrate, a first semiconductor layer having a first conductive type formed on the first gate conductive layer, a source conductive layer and a drain conductive layer electrically isolated from each other and positioned on the first semiconductor layer, a second semiconductor layer having a second conductive type formed on the source conductive layer and the drain conductive layer, and a second gate conductive layer formed on the second semiconductor layer. The first conductive type is complementary to the second conductive type.