A control apparatus for a rotating electric machine is provided. The rotating electric machine includes a moving portion that applies torque to a drive shaft of an internal combustion engine. The control apparatus acquires a rotational frequency signal that is a signal that changes depending on a rotational frequency of the moving portion per unit time. The control apparatus calculates a damping torque that is applied from the moving portion to the drive shaft to suppress vibration during operation of the internal combustion engine. The control apparatus calculates the damping torque based on the rotational frequency signal acquired by the signal acquiring unit in response to the rotating electric machine performing cranking of the internal combustion engine.