At this stage,the development of the automotive industry is very rapid,and the number of cars is increasing,and the ensuing global energy crisis and environmental pollution are becoming more and more serious.So the development of automobile lightweight has become the only way for the sustainable development of the automobile industry.In this paper,glass fiber reinforced polypropylene(GFRPP)composite material is used instead of sheet metal as the fan cover material.According to the size,main assembly relationship,and requirements of a domestic automobile fan cover,the design principle of all-plastic automobile fan cover is determined without affecting performance,and the design of automotive fan cover is completed.CATIA software is used to establish a three-dimensional geometric model.With reference to the design principles and molding process of injection molded products,the molding process is analyzed by Moldflow software to study the influence of relevant parameters.The resulting all-plastic fan cover can be molded integrally while meeting the design requirements of the whole vehicle,reducing the weight of the traditional sheet metal fan cover by 42.5%.