The purpose of the invention is to countermeasure a disconnection between the drain electrode or the source electrode and the wiring or the electrode formed on the insulating film via through hole. The concrete structure is that: A display device having a display area including a plurality of pixels comprising: the pixel includes a thin film transistor having a semiconductor layer as an active element, a first insulating film is formed to cover a drain electrode of the thin film transistor, the drain electrode is connected with an electrode or an wiring that are formed on the first insulating film via a through hole, an oxide semiconductor layer exists between the drain electrode and the first insulating film, the oxide semiconductor layer does not exist at the bottom of the through hole.