The steering device includes first and second motors for steering which have common electric characteristics； first and second current sensors detecting first and second current values in the first and second motor, respectively； and abnormality diagnosis units. The abnormality diagnosis units make an abnormality diagnosis indicating that the steering device is abnormal when difference between the first and second current values exceeds a predetermined threshold value. When some abnormality occurs in the current detecting units for detecting the magnitudes of a current flowing through the steering motor, an abnormality diagnosis is rapidly made by comparing the difference with the predetermined value.
