A semiconductor device which shifts a low-level signal is provided. In an example, a first transistor including a first terminal electrically connected to a first wiring and a second terminal electrically connected to a second wiring, a second transistor including a first terminal electrically connected to a third wiring and a second terminal electrically connected to the second wiring, a third transistor including a first terminal electrically connected to a fourth wiring and a second terminal electrically connected to a gate of the second transistor, a fourth transistor including a first terminal electrically connected to a fifth wiring, a second terminal electrically connected to a gate of the third transistor, and a gate electrically connected to a sixth wiring, and a first switch including a first terminal electrically connected to the third wiring and a second terminal electrically connected to a gate of the first transistor are included.