In view of the concrete dam monitoring data in monitoring model is less，high dimension and nonlinear degree as well as the method of stepwise regression forecast value volatility，part of the measuring value loss can cause such problems as poor fitting effect，support vector machine(SVM)can effectively solve the problem of small sample，high dimension and nonlinear.So，support vector machine was used in the simulation of the concrete dam monitoring model of hydraulic component，and stepwise regression method is used to simulate the water pressure component with a combination and simulation of the temperature component and aging component to build the dam monitoring model based on the combination method of SVM-stepwise regression，then give a comparison and analysis between stepwise regression-stepwise regression model，SVM-SVM model and stepwise regression-SVM model，results show that the SVM-concrete dam safety monitoring model of combination of stepwise regression fitting precision is high，the forecast effect is good，this model will be more suitable for dam monitoring model.