A pulley for a continuously variable transmission is provided with a fixed half-pulley fitted on a supporting shaft and a mobile half-pulley, which is able to slide towards the fixed half-pulley under the thrust of a spring, so as to define a V-shaped race of variable amplitude. The pulley is further provided with a device for compensating the axial thrust, said device being constituted by a cam and a cam follower, which are coupled in contact with one another to impart an additional axial thrust on the mobile half-pulley in response to a torque acting on the pulley. The cam is defined by a tubular body made of plastic material co-moulded on the supporting shaft, whilst the cam follower is made of a single piece with the mobile half-pulley.