The invention relates to a one-way belt wheel, in particular to a roller friction type one-way belt wheel for an automobile generator. The roller friction type one-way belt wheel comprises a belt wheel body and a sleeve, wherein the belt wheel body is arranged on the outer ring of the sleeve in a sleeving mode, the belt wheel body and the sleeve are coaxially arranged, and a first positioning bearing and a second positioning bearing are sequentially arranged in the inner hole of the belt wheel body in the axial direction. The roller friction type one-way belt wheel is characterized in that a one-way clutch assembly is arranged between the first positioning bearing and the second positioning bearing and comprises an inner ring, an outer ring, rollers, supporting springs and retainers, wherein the inner ring is tightly arranged on the outer circle of the sleeve in a sleeving mode, a plurality of grooves are uniformly formed in the surface of the inner ring, every two adjacent grooves are connected through an arc-shaped groove, each groove is provided with an arc-shaped working face, and the circle center corresponding to each arc-shaped working face is deviated from the center of the inner ring. According to the belt wheel, the problems of friction heating and fracturing of the supporting springs can be avoided, the noise can be effectively reduced, and the service life of the one-way belt wheel can be prolonged.