A method for manufacturing a thin film transistor (TFT) includes the steps of: providing a substrate (1); and forming a TFT circuit on the substrate using laser-induced chemical vapor deposition (LCVD). Detailedly, the method includes providing the bare substrate, cleaning the substrate with cleaning liquid, and successively forming a gate electrode (2), a gate oxide layer (3), a source electrode (5), and a drain electrode (6) on the substrate by LCVD, thus obtaining the thin film transistor. The forming steps may be controlled by one or more computer programs. The LCVD can be pyrolytic LCVD, photolytic LCVD, or photophysical LCVD. The method is simple and inexpensive.