To provide a device for detecting toque anomalies capable of reliably detecting torque anomalies even in the case that torque change time is equal to one cycle of current or less.

Three-phase currents supplied for a three-phase A.C. motor are simultaneously detected. When the at least single-phase current value of the three-phase currents exceeds a predetermined threshold value, it is determined that torque is anomalous. In the case that it is normal, a torque determination normal signal is outputted. In the case that it is anomalous, at least either a first torque anomaly signal which indicates a torque anomaly on the side of a positive current or a second torque anomaly signal which indicates a torque anomaly on the side of a negative current is outputted.