Abstract: Toothed belt in which the toothed part is covered with a fabric consisting of a warp and a weft consisting of weft threads formed by an elastic thread, preferably made from polyurethane, acting as the core, and by at least a pair of composite threads wound on the elastic thread. Each composite thread comprises a thread with high heat resistance and high strength, preferably made from para-aromatic polyamide, and a covering thread, preferably made from nylon, wound on the thread with high heat resistance and high strength. The structure of the weft of the toothed belt is such that each thread with high heat resistance and high strength can be completely isolated in such a way that it is not damaged by the friction of the belt against the teeth of the pulley, ensuring a greater durability of the belt. The structure with a pair of composite threads also makes it possible to increase the breaking load of the fabric.