An artificial knee joint including a femoral component to be attached to a femur and a tibial component to be attached to a tibia, wherein in the femur component a medial condyle thereof is thicker than a lateral condyle thereof; in the tibial component, a medial articular surface thereof, which supports the medial condyle of the femur component, is thinner or deeper than a lateral articular surface thereof, which supports the lateral condyle of the femur component; and a joint line joining the lowest points of contact surfaces between the medial and lateral condyles of the femur component and the medial and lateral articular surfaces of the tibial component in a longitudinal cross section in a medial-lateral direction is inclined inward at virtually the same angle over the entire region of an angle of flexion-extension.