In order to shorten the product development cycle and reduce the number of mold trials, the UAV camera lens cover of acrylonitrile-butadiene-styrene terpolymer (ABS) material was taken as the research object, and the mold flow analysis of the whole injection molding process was carried out based on Moldflow software. The optimal gate position was determined by the filling time of the lens cover, the temperature of the flow front, the weld mark and the cavitation. The feasibility of optimizing the cooling system was determined by the temperature difference of the coolant and the temperature difference of the loop pipe wall. The optimal molding parameters of the plastic parts were obtained by analyzing the three forming windows of mass, maximum shear rate and maximum shear stress. Finally, the parameters were verified by warpage deformation analysis. Based on the simulation results and the production requirements of the plastic parts, the injection molding machine that met the molding requirements was selected. Through the check of the clamping force, the maximum injection capacity and the injection pressure, it was proved that the selected injection molding machine fully meets the design requirements. Finally, based on the results of mold flow analysis, a set of three-plate mold side core-pulling structure injection mold with one mold and two cavities was designed. The results show that Moldflow software analysis can effectively improve the design efficiency and quality of UAV camera lens cover, shorten the production cycle of the product, and guide the mold design of similar products.