The present invention relates to a method of fabricating a thin film transistor in which a metal silicide line generated from Metal Induced Lateral Crystallization is located at the outside of a channel region. The present invention includes the steps of forming a semiconductor layer on a substrate wherein the semiconductor layer has a first region, a channel region and a second region in order, forming a gate insulating layer/a gate electrode on the channel region, doping the first and the second region heavily with impurity, forming a metal film pattern making the first region a metal-offset, and crystallizing the semiconductor layer by means of applying thermal treatment to the semiconductor layer having the metal film.