The invention relates to a manufacturing method of a sports competition hovercraft hull, belongs to a production method of a sea race hovercraft hull, and mainly is used for solving the problems that a conventional hovercraft hull manufacturing method is long in period, complex in process, high in labor intensity, high in technical requirements and unstable in quality. The technical scheme adopted by the invention comprises that the manufacturing method of the sports competition hovercraft hull comprises the manufacturing steps: 1) preparing the hull from the following raw materials by the weight percentage: 50-65% of linear low-density polyethylene, 10-15% of medium-density polyethylene and 20-40% of polyethylene; 2) crushing the raw materials into particles with the particle size of 30-70 mesh, and mixing evenly; 3) carrying out drying treatment of a mold; 4) mixing the raw materials with a pigment; 5) pouring the powder into the mold, and carrying out rotational molding; 6) heating up, and carrying out heat preservation; 7), molding and cooling; 8) after the mold is cooled for 25 min, injecting a polyurethane foaming material, and 30 min later, taking the hull out from the mold.