A negative pressure pump has: a housing; a rotating shaft having a shaft portion, and a supporting portion; a vane that is supported at the supporting portion so as to freely move reciprocally in a direction orthogonal to the rotating shaft, and that rotates integrally with the rotating shaft, and whose end portions slide on an inner wall surface, and that sections an interior of the housing into plural spaces; an intake portion that is formed in the housing; a discharging portion that is formed further toward a vane rotating direction downstream side than the intake portion; and a concave portion that is formed in a bottom surface between the discharging portion and a curved surface in a vane rotating direction, and that communicates with a circular hole, and guides the lubricant, that is moved by the vane, to the circular hole.