To produce a V-ribbed belt without generating a large quantity of ground rubber refuse.

An unvulcanized rubber sheet 4 is superposed on a press mold 2 having a large number of preforming V-grooves 1 provided thereto through a resin film 3 to be pressed to the mold 2 to shape preparatory V-ribs 5 on the surface of the rubber sheet 4 having the resin film 3 superposed thereon. A cylindrical split mold having a large number of molding V-grooves provided to the outer periphery thereof in the peripheral direction and divided into a plurality of parts in the peripheral direction to be made foldable and capable of being reduced in diameter by folding is used and the rubber sheet 4 is wound around the outer periphery of the split mold so that the resin film 3 comes into contact with the split mold and the preparatory V-ribs 5 are fitted in the molding V-grooves. Subsequently, the whole is covered with a jacket to perform vulcanization to mold a sleeve-shaped molded object and the split mold is folded to take out the sleeve-shaped molded object from the outer periphery of the split mold.