To provide a compact magical planetary roller type reduction gear in which skew is reduced and has a small number of parts.

In the magical planetary roller type reduction gear, a large diameter part 4a of a side of planetary roller 4 with a small diameter part 4c formed in it is pressure welded to a fixing wheel 5 and a sun roller 3a, another large diameter part 4b is pressure welded to the sun roller and power from a differential wheel 6 circumscribed to the small diameter part is output or input. A guide 3b for preventing movement of the planetary roller in the axial direction is provided on the main shaft. In a carrier 7, 4% or more of circumference surfaces 4a, 4b of the planetary roller respectively slide and contact and are formed opposite to each other along a direction approximately perpendicular to a revolution surface 30 of the planetary roller shaft. In addition, a pocket 27 with a facing surface 28 as a fine clearance to hold a circumference surface of the planetary roller without burn is provided for the carrier 7 and both side plates 7b are provided so that it is possible to respectively form clearances 42 between both end surfaces 28 of the planetary roller and both the side plates 7b.

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