A semiconductor device including a display pixel circuit and an imaging pixel circuit is provided. The semiconductor device includes first and second circuits; the first circuit includes a light-emitting device; and the second circuit includes a light-receiving device, first to fifth transistors, and a first capacitor. The light-receiving device includes first and second terminals, and the light-emitting device includes third and fourth terminals. A first terminal of the first transistor is electrically connected to a first terminal of the second transistor, and a gate of the second transistor is electrically connected to a first terminal of the third transistor and a first terminal of the first capacitor. A second terminal of the first capacitor is electrically connected to a first terminal of the fourth transistor and a first terminal of the fifth transistor. A second terminal of the fifth transistor is electrically connected to the first terminal of the light-receiving device, the second terminal of the light-receiving device is electrically connected to the third terminal of the light-emitting device, and the fourth terminal of the light-emitting device is electrically connected to a wiring.