POWER TRANSMISSION DEVICE

A power transmission device includes a motor including a rotor, a first planetary reduction gear connected downstream of the motor, a second planetary reduction gear connected downstream of the first planetary reduction gear, a differential gear connected downstream of the second planetary reduction gear, and a drive shaft connected downstream of the differential gear. The first planetary reduction gear includes a sun gear and a pinion gear that is a stepless pinion. The second planetary reduction gear includes a sun gear and a pinion gear that is a stepped pinion. The drive shafts is penetrating an inner circumference of the rotor of the motor, an inner circumference of the sun gear of the first planetary reduction gear, and an inner circumference of the sun gear of the second planetary reduction gear.