In an in-wheel motor drive device, a speed reduction part is a parallel shaft gear reducer that includes a plurality of gear shafts extending in parallel to one another. One of the gear shafts is coupled with the rotation shaft of the motor part, the other one of the gear shafts is coupled with the wheel hub of the wheel hub bearing part. Remaining gear shafts decelerate the rotation of the motor part and transmit it to the wheel hub. The motor drive device includes a parking gear attached to any of the gear shafts. The parking pawl has a projection portion engaged with a recess portion of the parking gear. A movement member enables a parking pawl to move between a locking position engaged with the recess portion and an unlocking position not engaged therewith. The parking gear, the parking pawl, and movement member are housed inside a housing.