Disclosed are a single rotor-type axial gap motor with low magnetic loss and high output, and a pump device using the axial gap motor. A first contact surface (231) is provided on the lateral surface in one circumferential direction of a yoke strip (23), and a second contact surface (232) is provided on the lateral surface in the other circumferential direction of the yoke strip (23), wherein the first contact surface (231) and the second contact surface (232) are aligned with each other. Defining As1 and As2 as the surface areas (As) of the first and second contact surfaces (231, 232), and Ap1 and Ap2 as the projected surface areas (Ap) of the lateral surfaces of the aforementioned yoke strip seen from the circumferential direction, it holds that As>Ap.