Abstract: Newton-Raphson method and Quasi-Newton method are applied to the solution of node mathematicalmodel for natural gas pipeline network, and then Monte-Carlo method is used to solve the model.The l0wtimes results of which are respectively used as the node pressure initial values of Newton-Raphson methodand Quasi-Newton method.Compared with the single method, the improved method can obviously increasethe efficiency of calculation that the time of calculation is minimized effectively.