The nonlinear combustion instability process in liquid rocket engine is simulated. The gas controlling Navier-Stokes equations are described under the Euler coordinate.The liquid phase controlling equations are described under the Lagrangian coordinate.The two phase influences of gas and liquid are through the sources of equations.The sequential and parallel codes are written,and the codes are tested in parallel virtual machine environment.The results show that the parallel computation efficiency is reeasonably high.