Abstract: An artificial heart comprising two ventricles (8) and two atria (9) adapted for inclusion in a blood circulation system via valves (17), to operate in the same manner as a live heart. The heart comprises a rigid housing (1) containing in its top part two inlet ports (2) and two outlet ports (3). Elastic ventricle (8) and elastic atrium (9) constitute a symmetrical half of the heart. The bottom part of housing (1) is shaped in the form of two parallel cylinders (4) capped tightly and slidably with buckets (5) having convex bottoms, these bottoms forming pistons (6). An elastic movable diaphragm (7) is located above each piston (6), and is circumferentially attached to the inside of cylinder (4) and to the elastic ventricle (8). Physiological liquid is contained between ventricle (8) and diaphragm (7).