According to one embodiment, a display device includes an insulating substrate, a first insulating film, a second insulating film, a third insulating film, a fourth insulating film, a fifth insulating film, a sixth insulating film, a color filter layer, a semiconductor layer disposed between the second insulating film and the third insulating film, and a gate electrode disposed between the third insulating film and the fourth insulating film, wherein the first, fourth, and sixth insulating films are formed of a silicon nitride, and the second, third, and fifth insulating films are formed of a silicon oxide.