An electric power steering apparatus having an electric motor that includes two mutually independent armature windings (21, 22) and assisting steering power of a driver who controls steering of a vehicle using a driving force of the electric motor, wherein the electric power steering apparatus includes two control units (1a, 1b) that drive the electric motor, the first control unit controls power supplied to the first armature winding and the second control unit controls power supplied to the second armature winding, each of the two control units (1a, 1b) includes a power supply circuit (13a, 13b), an input circuit (12a, 12b) into which input information including at least steering torque applied to the steering of the vehicle by the driver is input, an inverter circuit (3a, 3b) configured so as to drive the electric motor, a drive circuit (11a, 11b) configured so as to drive the inverter circuit (3a 3b), and a CPU (10a, 10b) that inputs a control command based on a control amount computed based on the input information output from the input circuit (12a, 12b) into the drive circuit (11a, 11b), the power supply circuit (13a, 13b) is configured so as to supply power to the control unit (1a, 1b) to which the power supply circuit (13a, 13b) itself belongs, the CPU (10a, 10b) provided in each of the two control units (1a, 1b) is configured so as to be able to acquire the input information of the control unit (1a, 1b) to which the CPU (10a, 10b) itself does not belong, has an abnormality detecting function of detecting an abnormality related to the input information of the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs and an abnormality related to information other than the input information, and is configured so as to transmit the control command to the drive circuit (11a, 11b) of the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs at a normal time when none of the abnormalities is being detected, when one CPU (10a, 10b) of the individual CPUs (10a, 10b) detects an abnormality related to the input information of the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs, the one CPU (10a, 10b) that detects an abnormality related to the input information is configured so as to compute a control amount using the input information of the control unit (1a, 1b) to which the CPU (10a, 10b) itself does not belong, and transmit a control command based on the computed control amount to the drive circuit (11a, 11b) in the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs, and the other CPU (10a, 10b), which is not detecting an abnormality related to the input information, is configured so as to continuously transmit a control command equivalent to that at the normal time to the drive circuit (11a, 11b) in the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs, when one CPU (10a, 10b) of the individual CPUs (10a, 10b) detects an abnormality related to information other than the input information of the control unit (1a, 1b) to which the CPU itself belongs, the one CPU (10a, 10b) that detects an abnormality related to information other than the input information is configured so as to transmit a control command to carry out either a stopping or a continuation of a drive of the electric motor in accordance with details of the detected abnormality to the drive circuit (11a, 11b) in the control unit (1a, 1b) to which the CPU (10a, 10b) itself belongs, the other CPU (10a, 10b), which is not detecting an abnormality related to information other than the input information, is configured so as to transmit a control command in accordance with the details of the abnormality detected by the one CPU (10a, 10b) to the drive circuit (11a, 11b) in the control unit (1a, 1b) to which the CPU itself belongs, and the drive circuit (11a, 11b) provided in each of the two control units (1a, 1b) is configured so as to drive the inverter circuit (3a, 3b) to which the drive circuit (11a, 11b) itself belongs so as to control the electric motor based on the transmitted control command.