Disclosed is a pressure sensor comprising: a substrate; a pressure reception plate which is provided in a state of facing the substrate, the pressure reception plate comprising in a surface which faces the substrate, a low reflection region, and a high reflection region having a relatively higher reflection ratio compared to the low reflection region; a support portion to change a distance between the substrate and the pressure reception plate when a pressure is applied to the pressure reception plate, the support portion being provided in between the substrate and the pressure reception plate; and a plurality of light receiving elements which are respectively provided on the substrate in positions facing the low reflection region and in positions facing the high reflection region, of the pressure reception plate.