To improve the accuracy of the optimization parameters of the cyclone and obtain the optimal solution in structure optimization, a new type of composite hydrocyclone was taken as the research object, the single factor analysis optimization method based on correlation analysis was used to guide the selection of optimization range and improve the accuracy of optimization range of structural parameters. Based on the response surface optimization method, the optimal structural parameters of the hydrocyclone were determined with the separation efficiency as the optimization objective, and the regression model between the separation efficiency and the structural parameters was obtained. The results show that the significant relationship between different structural parameters and each performance index is not the same. According to the results of correlation analysis, the optimal range of each structure is as follows. The upper cone angle is 0° ~ 4°, the lower cone angle is 8° ~ 12°, and the diameter of the bottom nozzle is 12 ~ 16 mm. The optimal structure of the cyclone obtained by response surface optimization is as follows: the upper cone angle is 2.565°, the lower cone angle is 11.719°, and the diameter of the bottom flow port is 12.889 mm. Under these parameters, the solid separation efficiency of the hydrocyclone reaches 99.945%, and the gas separation efficiency reaches 93.807%. It provides a new method to optimize the structure of hydrocyclones.