A magnetic load sensor unit comprising: a flange member configured to be deflected in the axial direction when an axial load is applied thereto; a support member supporting the flange member; at least one magnetic target which generates a magnetic field; and at least one magnetic sensor for detecting a magnetic field generated by the magnetic target; wherein one of the magnetic target and the magnetic sensor is fixed to the flange member and the other is fixed to the support member, such that when the flange member is deflected, the magnetic target and the magnetic sensor move relative to each other, whereby a magnitude of the load applied is detectable based on a magnetic field as detected by the magnetic sensor, wherein the flange member and the support member are annular plate members facing each other, wherein the support member supports a radially outer portion of the flange member, wherein the flange member includes a tubular portion having a radially outer surface facing a radially inner surface of the support member, the magnetic target is fixed to the radially outer surface and the magnetic sensor is fixed to the radially inner surface when the magnetic target is fixed to the flange member and the magnetic sensor is fixed to the support member or the magnetic target is fixed to the radially inner surface and the magnetic sensor is fixed to the radially outer surface when the magnetic target is fixed to the support member and the magnetic sensor is fixed to the flange member, characterized in that: the flange member has a spherical surface having a center located on a center axis of the flange member, and wherein the magnetic load sensor unit is configured such that an axial load acts on the spherical surface. a flange member configured to be deflected in the axial direction when an axial load is applied thereto; a support member supporting the flange member; at least one magnetic target which generates a magnetic field; and at least one magnetic sensor for detecting a magnetic field generated by the magnetic target; wherein one of the magnetic target and the magnetic sensor is fixed to the flange member and the other is fixed to the support member, such that when the flange member is deflected, the magnetic target and the magnetic sensor move relative to each other, whereby a magnitude of the load applied is detectable based on a magnetic field as detected by the magnetic sensor, wherein the flange member and the support member are annular plate members facing each other, wherein the support member supports a radially outer portion of the flange member, wherein the flange member includes a tubular portion having a radially outer surface facing a radially inner surface of the support member, the magnetic target is fixed to the radially outer surface and the magnetic sensor is fixed to the radially inner surface when the magnetic target is fixed to the flange member and the magnetic sensor is fixed to the support member or the magnetic target is fixed to the radially inner surface and the magnetic sensor is fixed to the radially outer surface when the magnetic target is fixed to the support member and the magnetic sensor is fixed to the flange member,