To solve a problem in an electric power steering device provided with a motor for giving an auxiliary force to a steering shaft to control its torque wherein steering wheel operation becomes heavy suddenly because the control of the electric motor is immediately stopped for safety when detecting an abnormality and it is dangerous on the contrary.

When the contents of abnormality are an abnormality of a position (angle detection) sensor 22 of the electric motor 20 and an abnormality of a current of one phase of the electric motor 20, the control of the electric motor 20 is not stopped immediately even when detecting an abnormal condition, and the control of an angle of the electric motor at which angle detection of the position sensor 22 is effective or an effective current of a winding wire is continuously performed to ensure a torque output in a certain angle scope of the electric motor and ensure an auxiliary force.