To provide an inexpensive planetary roller type power transmission device, achieving favorable lubrication and good for high-speed rotation.

In this planetary roller type power transmission device 23, two or more planetary rollers 3' are interposed in pressure contact state between the outer peripheral surface 1a of a sun roller shaft 1 and the inner peripheral surface 2a of a fixed ring 2, and a carrier shaft 4 is provided to equally divide the planetary rollers and support the same. The side plates 5, 6 regulating the axial movement of the planetary rollers are provided with ring-like oil reservoirs 7, 8, 9 having opening parts 7a, 8a, 9a opened to the end faces 3a, 3b of the planetary rollers. The ring-like oil reservoirs 8, 9 are disposed so that the inside diameter side ends 7b, 9b are located inside the inner peripheral surface of the fixed ring, and the outside diameter side ends 8c, 8d are abutted on the end face of the fixed ring. The ring-like oil reservoir 7 is disposed inside the inner peripheral surface of the fixed ring, and the opening part 7a is gradually isolated from the planetary rollers as it goes from the outside diameter side toward the inside diameter side. Further, the device is provided with communicating passages 11, 12, 13 communicating the oil reservoirs with the outside of the side plate. Further, a lubrication ring formed of an oil impregnation member is fitted.