A pressure sensor which detects variation in pressure, the pressure sensor including a cantilever which bends according to a pressure difference between the inside and the outside of a cavity in a sensor main body, and a first gap, a second gap, and a third gap which are formed on a proximal end portion of the cantilever. The first to third gaps electrically partition the proximal end portion of the cantilever into a first support portion, a second support portion, a first displacement detection portion, and a second displacement portion in a second direction orthogonal to a first direction in which the proximal end portion and a distal end portion of the cantilever are connected to each other in plan view. The first and second displacement detection portions detect displacement according to the bending of the cantilever between the first and second support portion.