The invention discloses a manufacturing method of high-tenacity polyphenyl thioether composite granules. The polyphenyl thioether resin premix added with an addition agent is fully evenly mixed in a homo-mixer, and then the granule product is manufactured by subsequent extrusion and mixing processing. The granule comprises a proportion of polyphenyl thioether resin treated with oxidized thermal crosslinking, and is added with 5-35% of toughening modifier, 0.1-1 percent of anticorrosion inhibitor and 0.1-5 percent of thermal forming stabilizer fatty alcohol polyoxy styrene ether phosphoester amine salt; the premix obtained by fully evenly mixing all the materials in the homo-mixer and the fiber glass with the weight of 30-35 percent of that of the premix are mixed together and extruded for forming and chopping by an equidirectional double screw extruder. Finally, the high-tenacity polyphenyl thioether composite granules which have resistance to shock, stable thermotropy and excellent tensile strength are obtained.