A motor control apparatus comprising: a motor electric angle estimating unit that estimates a motor electric angle of a multi-phase electric motor based on a steering angle detected by a steering angle detecting unit that detects the steering angle, where the multi-phase electric motor generates a steering assist force; and a motor driving control unit that controls driving of the multi-phase electric motor based on a motor electric angle detected by a motor electric angle detecting unit that detects the motor electric angle when the motor electric angle detecting unit is normal, and controls the driving of the multi-phase electric motor based on a motor electric angle estimate estimated by the motor electric angle estimating unit when the motor electric angle detecting unit is abnormal; characterized by a shift amount measuring unit which, when the motor electric angle detecting unit is normal, measures a relationship of a value related to output torque of the multi-phase electric motor and a shift amount between the motor electric angle detected by the motor electric angle detecting unit and the motor electric angle estimate, which is caused by mechanical elements standing between the steering angle detecting unit and the multi-phase electric motor ; a shift amount storing unit that stores the relationship of the value related to the output torque and the shift amount, which is measured by the shift amount measuring unit; and a motor electric angle correcting unit (64 to 67) that corrects the motor electric angle estimate based on the shift amount stored in the shift amount storing unit and corresponding to the value related to the output torque when the motor electric angle estimate is estimated. a motor electric angle estimating unit that estimates a motor electric angle of a multi-phase electric motor based on a steering angle detected by a steering angle detecting unit that detects the steering angle, where the multi-phase electric motor generates a steering assist force; and a motor driving control unit that controls driving of the multi-phase electric motor based on a motor electric angle detected by a motor electric angle detecting unit that detects the motor electric angle when the motor electric angle detecting unit is normal, and controls the driving of the multi-phase electric motor based on a motor electric angle estimate estimated by the motor electric angle estimating unit when the motor electric angle detecting unit is abnormal; characterized by a shift amount measuring unit which, when the motor electric angle detecting unit is normal, measures a relationship of a value related to output torque of the multi-phase electric motor and a shift amount between the motor electric angle detected by the motor electric angle detecting unit and the motor electric angle estimate, which is caused by mechanical elements standing between the steering angle detecting unit and the multi-phase electric motor ; a shift amount storing unit that stores the relationship of the value related to the output torque and the shift amount, which is measured by the shift amount measuring unit; and a motor electric angle correcting unit (64 to 67) that corrects the motor electric angle estimate based on the shift amount stored in the shift amount storing unit and corresponding to the value related to the output torque when the motor electric angle estimate is estimated. <EOS>