In this paper, through analyzing the resin state, the numerical simulation is built for the Sandwich and the surrogate model is used to explore the influence of the thermal expansion coefficient of the mold and panel, the elastic modulus of the panel, the honeycomb size and other parameters on the shrinkage and roundness error during curing process. First of all, the finite element method is used to simulate the stress and deformation of the sandwich during curing process. Among them, the honeycomb equivalent model is established and the life and death cell technology is applied to perform equivalent modeling of the resin state change. The simulation results match the actual. The results show that the state change of the resin during molding is the main factor affecting the shrinkage of the sandwich structure. Secondly, the relationship between the shrinkage rate or roundness error and the influencing parameters is established by using the radial basis function (RBF). Finally, the sensitivity of the influence parameters of the shrinkage and roundness error is discussed. The results show that the thermal expansion coefficient of the mold and the thermal expansion coefficient of the panel are the most sensitive to the shrinkage of the sandwich structure and the most sensitive factor affecting the roundness error of the sandwich structure is the coefficient of thermal expansion of resin.