Abstract: An algorithm is developed based on the N-R(Newton-Raphson) iteration method to solve the nonlinear mathematical model of turbofan engine.It enhances the ability to search for the nonlinear equation solutions within a limited domain,which is dcsignated around the initial guess of solution and covers the genuine solution.Three iteration factors defined in this algorithm can be automatically readjusted by programming.Accordingly,the least times of iteration and corresponding optimum iteration factors can be found out from the program.