To provide a rear shock absorber arrangement structure for a motorcycle having no limitation on the arrangement flexibility and shape of a storage chamber. In a rear shock absorber arrangement structure for a motorcycle, including a unit swing type power unit U swingably connected to a body frame F and rotatably supporting a rear wheel WR, a rear shock absorber suspends the power unit from the body frame F. A storage chamber is disposed above the rear wheel WR. A lower end of the rear shock absorber is brought into connection at a position lower than the wheel-axle O provided in the power unit U as viewed from the side of the vehicle. An upper end of the rear shock absorber is connected to a portion lower than the storage chamber and near a bottom portion of the storage chamber.