Abstract: To provide an artificial heart valve capable of aiding the functions of the mitral valve of a patient in a minimally invasive manner. An artificial heart valve 1 which includes a valve leaflet securing part 2 and valve leaflets (a first valve leaflet 5 and a second valve leaflet 7), and in which the valve leaflets are connected to the valve leaflet securing part 2 at the top portion of the artificial heart valve 1, the valve leaflets each have a region which narrows in width toward the bottom of the leaflet, and the artificial heart valve is an artificial mitral valve or an artificial tricuspid valve.