Abstract: A centrifugal planetary friction transmission comprising an input shaft, an output shaft, at least one planetary friction pulley set which is formed by three coaxially linked cylindrical external friction pulleys, and three internal pulleys. The friction forces acting on the planetary friction pulley set are mostly cancelled out by each other. According to the invention, the external friction pulleys only contact with the internal friction pulleys, and the normal pressure for producing the friction force for transmitting the torque is created by the centrifugal force of the external friction pulley set only and the transmission is a positive characteristic planetary transmission.