To provide a centrifugal type blood pump apparatus which rotates an impeller in a non-contact condition with a housing by using a so-called dynamic pressure groove, keeps a distance between the impeller and the housing, and generates only little hemolysis.

The centrifugal type blood pump apparatus 1 is equipped with a housing 20, a centrifugal pump 2 having an impeller 21 rotating in the housing 20 for transporting blood, an impeller torque generating part 3 sucking and rotating the impeller 21, and a third magnetic material 41 sucking the impeller 21 in a direction opposite to the sucking direction by the impeller torque generating part 3. The suction force applied to the impeller 21 in the centrifugal pump 2 by the part 3 is balanced with the suction force by the third magnetic material 41 in the neighborhood of the center inside the housing 20, and the centrifugal type blood pump apparatus is equipped with a first dynamic pressure groove 38 provided on the inner surface of the housing on the side of the impeller torque generating part and a second dynamic pressure groove 71 provided on the inner surface of the housing on the side of the third magnetic material.