PURPOSE: To provide a magnetic bearing device reducing the rotation unevenness of a rotating body pivotally supported.

CONSTITUTION: This magnetic bearing device 1 where magnets 6 and 14 are arranged to respectively be opposed to the rotating body 11 and a bearing part and which pivotally supports the rotating body 11 without contacting by magnetic force between respective magnets 6 and 14 is provided with a projected part 15 at either of the opposed parts of respective magnets 6 and 14 and a recessed part 14a in which the projected part 15 is immersed in a non-contact state at the other side. By this constitution, the positional deviation of the rotating body 11 from the bearing part is prevented by a magnetic action between the projected part 15 and the recessed part 14a in the non-contact state and the rotation unevenness of the rotating body is reduced.