PURPOSE: To reduce the running cost by facilitating the mounting and removal of a planetary roller or a planetary shaft.

CONSTITUTION: The carrier 54 of a planetary roller type power transmission 5 is composed of a body 56, which has open windows 561 for storage of planetary rollers at several places at the circumference, and a planetary shaft 57 which is suspended between the two inwall faces 563 and 564 opposite to each other in axial direction in the open widow 561 of the body 56 and also on which a planetary roller 53 is set rotatably At one inwall face 564 is provided a recess 565, one end of which is set freely, and at the other inwall face 564 is provided a through hole 566, in which the other end of the planetary shaft 57 is set freely, and in this through hole 566, a screw 58 for stopping the slip out of the planetary shaft 57 is screwed into the opening on insertion side of the planetary shaft. Hereby, the planetary shaft 57 can be mounted on and removed from the body 56 easily by the operation of the screw 58.