The present disclosure relates to the field of liquid crystal display, and provides a method for manufacturing a TFT and the TFT thereof. The TFT includes: a base substrate; a gate electrode with a three-dimensional structure formed on the base substrate; a gate insulating layer for completely covering a top face and two side faces of the gate electrode; a semiconductor layer for completely covering a top face and two side faces of the gate insulating layer; a buffer layer for covering a top face and two side faces of the semiconductor layer at two ends of the semiconductor layer; and source and drain electrodes for completely covering a top face and two side faces of the buffer layer, wherein the semiconductor layer of the TFT is of a three-dimensional structure.