A heart-function simulator comprises: a tank that stores a fluid, a fluid intake port and a fluid outlet port being formed on the tank a unidirectional first valve that makes the fluid circulate from the tank a pump, further comprising a pumping chamber that aspirates and extracts the fluid by reciprocation of a reciprocal member, an aspiration port that introduces the fluid from the first valve into the pumping chamber, an extraction port that extracts the fluid from the pumping chamber, and a pump head whereon an aperture is formed that leads to the pumping chamber a closed-type first chamber that is connected to the aperture formed on the pump head of the pump and that adjusts compliance of the pump chamber according to the volume of air therein a unidirectional second valve that circulates the fluid from the tank and a piping path that circulates the fluid from the second valve to the intake port of the tank.
