A solenoid pump is equipped with a housing formed therein with a fluid passage through which a fluid flows from an inlet port to an outlet port, and a movable member, which is displaced based on an excitation state of a solenoid section, for thereby opening and closing the fluid passage. The fluid passage includes an inlet side passage that communicates with the inlet port, an outlet side passage that communicates with the outlet port, and a pump chamber made up of a space in communication with the inlet side passage and the outlet side passage, and surrounded by the housing and an end portion of the movable member. Accompanying displacement thereof, the movable member opens and closes communication between the pump chamber and the outlet side passage.