To provide a semiconductor device with high aperture ratio or a manufacturing method thereof, and to provide a semiconductor device with low power consumption or a manufacturing method thereof.

The semiconductor device comprises: a conductive layer having light transmission characteristics which functions as a gate electrode; a gate insulating film formed on the conductive layer having the light transmission characteristics; a semiconductor layer formed on the conductive layer having the light transmission characteristics which functions as the gate electrode via the gate insulating film; and a conductive layer having light transmission characteristics which is electrically connected to the semiconductor layer and functions as a source electrode or a drain electrode.