According to present invention, system on panel without complicating the process of TFT can be realized, and a light-emitting device that can be formed by lower cost than that of the conventional light-emitting device can be provided. A light-emitting device is provided in which a pixel portion is provided with a pixel including a light-emitting element and a TFT for controlling supply of current to the light-emitting element; a TFT included in a drive circuit and a TFT for controlling supply of current to the light-emitting element include a gate electrode, a gate insulating film formed over the gate electrode, a first semiconductor film, which overlaps with the gate electrode via the gate insulating film, a pair of second semiconductor films formed over the first semiconductor film; the pair of second semiconductor films are doped with an impurity to have one conductivity type; and the first semiconductor film is formed by semiamorphous semiconductor.