To provide a deformation correcting apparatus to correct the deformation with high accuracy while suppressing the irregular hardness caused by the irregular heating in correcting the deformation to be small.

In the deformation correcting apparatus, an annular member 1 is heated to a desired tempering temperature by a heater to correct the deformation while an outside diameter surface 1a of the annular member 1 is restricted by a correction die 2. The correction die 2 is formed of a non- magnetic material. The heater comprises a pair of heating cores 7 and 8, and heats the annular member 1 by nipping the annular member 1 in the width direction.