In this paper, by using the concepts " entropy production" and "excess entropy production", the Lyaponov stability of the master equation in linear and nonlinear range has been discussed. The results obtained are consistent with the stability theory of the time evolution equation of macroscopic non-equilibrium systems discussed by I. Prigo-gine. In addition, the concept of "probability flow" is proposed for the multivariable master equation of the stochastic model of non-equilibrium systems, and the method of decomposition of "probability flow" is given.