Electric power steering device

The present invention relates to an electric power steering device that detects steering torque transmitted by a steering shaft by means of a torque sensor, and provides steering assistance power in response to the torque detected by means of an electric actuator. In an electric power steering device, an actuator generates steering assistance power in response to torque transmitted by a steering shaft, the outer circumference of which is covered by a torque sensor detecting the torque. The rotation of the actuator is transmitted to the steering shaft by a reduction gear mechanism having a driven gear on the steering shaft, and a driving gear which engages with the driven gear. The torque sensor is disposed between the driven gear and the steering wheel. A housing has a portion which covers the steering shaft between the steering wheel and the torque sensor, and a portion which covers the torque sensor. The housing is formed by plastically deforming a single metal pipe.