A manufacturing method of a thin film transistor of the present invention includes the steps of (i) forming an electrode formation area in which a source electrode and a drain electrode are formed by applying a droplet of an electrode raw material, (ii) applying the droplet of the electrode raw material on drop-on positions located off a forming area of a semiconductor layer and in the electrode formation area, and (iii) forming the source electrode and the drain electrode in the electrode formation area. With this arrangement, it is possible to surely prevent adherence of a splash droplet on a channel section between each electrode, in forming the source electrode and the drain electrode by applying the droplet of the electrode raw material.