A feeding system of a pump-fed Liquid Propellant Staged Combustion Cycle Rocket Engine (LPSCCRE) is taken as a research object.Its system physical model is constructed

and its nonlinear mathematical model is established.The nonlinear dynamic response of LPSCCRE is simulated with adaptive Runge-Kutta algorithm on the conditions of parameter variation and working regime regulation in wide range.Comparison of the obtained results with the test data shows that:The mathematical model is quite valid and calculation method meets the simulation requirements.