A method of crystallizing polysilicon, a method of fabricating a thin film transistor using the same, and a method of fabricating a liquid crystal display thereof form a polysilicon layer having uniformly oriented crystalline grains with high quality. A polysilicon crystallizing method includes forming a polysilicon layer on a substrate, making grains of the polysilicon layer amorphous except a portion of the grains having specific orientation, and crystallizing the polysilicon layer using the grains having the specific orientation.