A semiconductor device includes: one or more leads; one or more semiconductor elements disposed on a first side in a thickness direction with respect to the one or more leads; a plurality of wires each of which is electrically connected to at least one of the one or more leads and the one or more semiconductor elements; and a sealing resin that covers the one or more semiconductor elements, the plurality of wires, and at least a portion of the one or more leads. The plurality of wires include a first wire and a second wire. The second wire is curved in a convex shape toward the first wire as viewed in the thickness direction. The second wire extends across the first wire as viewed in the thickness direction and is spaced apart from the first wire in the thickness direction.