The purpose of developing a virtual platform for system dynamic analysi s is to improve the safe reliability of the hydraulic push-up system embedding in 2030 new cold rolling skinpass mill while adjusting parameters during test-d rive. A mathematical model of hydraulic push-up system in skinpass mill is built based on AMEsim 8A, and the force servo state in the process of roller contact has been analyzed by Matlab／Simulink to verify the availability of this model. The numerical analysis on dynamic characteristics of variable gain in variable o il column in the process is completed then. Test results show that the response data of mathematical model coincides with actual measurements, which provides an important basis for adjusting control parameters in variable oil column in push-up system. The characteristics of the hydraulic model based on AMEsim include: reasonable boundary parameter settings, reliable dynamic process, practical simulation results.