A method of fabricating a thin film transistor includes forming an active layer on an insulating substrate; forming a gate insulation film on the insulating substrate; forming source, drain, and body contact regions which are separated by a channel region in the active layer; forming a gate on the gate insulation film; forming an interlayer insulation film on the insulating substrate; and forming source and drain electrodes electrically connected with the source and drain regions, respectively, wherein a voltage is applied to the channel region of the active layer through the body contact region, and the body contact region is connected to the source or drain electrode.