A display device includes a substrate, a display region, a peripheral region, an insulating layer which is disposed on a gate signal line and a conductor, a conductive layer which is disposed on the insulating layer and crosses a plurality of gate signal lines and the conductor in the peripheral region, a first semiconductor film which is disposed between the insulating layer and the conductive layer, and a second semiconductor film which is disposed between the insulating layer and the conductive layer and which is separated from the first semiconductor film. The conductive layer is connected to the plurality of gate signal lines via a plurality of diodes, and the plurality of gate signal lines are arranged in the display region and the peripheral region. A length of the conductor differs from a length of the gate signal line in the display region and the peripheral region.