To enhance precision of belt length, produce an accurate tooth profile and shorten forming time by preparing a belt having a small tooth pitch by reducing variations in rubber thickness and stabilizing the pitch line of a core wire by using a sail cloth having an unvulcanized rubber stuck thereon.

A manufacturing method for a double face-toothed belt comprises a vulcanizing process of making a vulcanized performed winding a tooth cloth 5' on an outer peripheral face of a grooved mold, spinning a core wire thereon, and forming a low tooth part by heating and pressurizing under a state wherein a rubber sheet 4' is laminated thereon; a grinding process of grinding the vulcanized preformed body until the core wire is exposed; and a finally forming vulcanizing process of heating and pressurizing a belt-like molded body 9 obtained by laminating the tooth cloth 5' to which the unvulcanized rubber 4' is stuck on a ground face by a press mold 22 having the same tooth shape of a specific pitch on upper and lower plates, and forming and vulcanizing an upper tooth part to form the double face-toothed belt.