In order to improve the structural stiffness of  press and ensure the accuracy of press body in working condition, for JH31-250 press, the optimal design method of the press body structure was explored, and the structural modal and static strength of the press body were analyzed by software Abaqus. Then, the conceptual configuration of the press body structure was optimized by the topology optimization technique, and based on this, the supporting structure of the two side walls was selected as the design domain for the configuration and size optimization. Furthermore, taking the geometric dimensions of the rectified press body ribbed slab structure as the optimization parameters and the relative displacement between workbench and crankshaft support hole of press body as the optimization target, the response surface model was established, the model was optimized by combining with particle swarm algorithm to obtain the optimal structural geometry parameters, and finally the optimized design of the press body structure was achieved. The optimization results show that there are obvious stress concentration phenomena on the inner side of press body and the front side of square hole before optimization, and the equivalent stress and the total displacement of the press body structure are reduced after optimization. The relative displacement between workbench and support hole is 0.2548 mm, the deformation amount is reduced by 40.03%, and the working accuracy of press body is improved. The dynamic analysis and verification of the optimized press body structure show that the optimized press structure does not resonate under various working vibration source frequencies, which meets the requirements for use. Thus, the researched structure can provide reference for the structural optimization of similar products.