A photosensor device includes a substrate, a graphene layer provided on the substrate, a pair of electrodes electrically connected to the graphene layer, and a passivation layer formed of a resin and configured to cover the graphene layer. The graphene layer has holes which are periodically arranged, and the passivation layer is provided with openings that communicate with the holes. The side surfaces of the holes and the inner walls of the openings are continuously covered with an insulating thin film.