To provide a motor-integrated magnetic bearing device that reduces a load capacity of an axial magnetic bearing, and improves the efficiency of a turbine.

The motor-integrated magnetic bearing device commonly uses rolling bearing 15, 16 which support radial loads, and a magnetic bearing 17 which supports either or both an axial load and bearing pilot pressure. The magnetic bearing 17 is mounted to a spindle housing 14, and made to oppose a thrust plate 13b composed of a ferromagnetic material arranged at a spindle 13 in a non-contact manner. A motor 28 is arranged at the spindle 13, and blower impellers 6a, 7a of a compressor 6 and a turbine 7 are mounted to both ends of the spindle 13. A large-diameter back face plate 22 larger than the back face of the turbine blower impeller 7a is mounted at the back face of the turbine blower impeller, and a difference between front faces and back faces of the blower impellers 6a, 7a is compensated. Nozzle plates 23 for introducing air into the turbine blower impeller 7a from the external peripheral side are arranged at a plurality of circumferential points of the turbine blower impeller 7a so as to oppose the surface of the back face plate 22.