Abstract: A manufacturing method for a thin film transistor (TFT) is provided. In the manufactured TFT, after a source structure, a drain structure and a channel structure are formed, a first photoresist layer is not removed and a second photoresist is formed on the first photoresist layer through which a semiconductor structure is formed. Further, n-type amorphous silicon, poly silicon or an organic metallic compound is used in replace of the conventional metal to form the source and drain structures so as to reduce step number of manufacturing for the TFT.