In order to analyze the comprehensive performance on hydraulic servo control system of gantry straightener, according to the system control model, on the basis of full consideration to the nonlinear factors of system, the comprehensive simulation analysis model is established by using SimMechanics modules and others in Matlab. The dynamic response characteristics of hydraulic servo control system were obtained. The results show that the modeling method is correct, which provides new method for optimization design of hydraulic servo control system of gantry straightener.