A belt-driven continuously variable transmission adapted to prevent an occurrence of belt slippage is provided. The continuously variable transmission comprises a hydraulic actuator formed on a back side of a movable sheave to change a belt groove between a fixed sheave and a movable sheave, and a torque cam assembly adapted to convert a torque into an axial thrust force by a relative rotation between a pair of cam members contacted to each other. In the belt-driven continuously variable transmission, a piston fitted onto a shaft of the driven pulley while allowing to rotate relatively therewith and to reciprocate thereon is integrated with one of the cam members of driven side and with an output gear for outputting torque of the pulley. The cam member of drive side is fixed in an axial direction on a driven shaft to be rotated integrally therewith.