There is provided a semiconductor device able to increase the mobility of carriers and reduce the current in the OFF state. The semiconductor device includes a gate electrode, an insulating layer on the gate electrode, a first electrode on the insulating layer, a second electrode on the insulating layer at an interval with the first electrode, an organic semiconductor layer disposed in the interval between the first electrode and the second electrode and covering at least part of the first electrode and the second electrode, and a first resistance layer formed on the organic semiconductor layer and having an electrical resistance lower than that of the organic semiconductor layer. The first resistance layer is formed from conductive polymers.