High-tenacity polypropylene filament polypropylene multifilament whose breaking strength is greater than 6cN/dtex. It has the characteristics of low relative density, low moisture absorption, high strength, wear resistance, acid and alkali resistance, and low thermal conductivity. Two-step and one-step wat silk technology can be used. The breaking strength of the silk produced by the two-step process is higher, reaching 6~8cN/dtex, and the silk produced by the one-step process has a strength of approximately 5~7cN/dex, but its energy consumption is low. It is an important fiber raw material for industrial textiles, used for high-speed sewing threads, luggage belts, straps for sports goods, geotextiles, ropes, nets, and fishing gear.