Abstract: The problem of stability of shock waves from thermodynamic piont of view is treated in this paper. Xu Fu discussed stability of shock waves in the sense of Landau and Lifshitz. In this paper we regard flow as a thormodynamic nonequlibrium system. On the basis of some principle of nonequlibrium thermodynamics we treat the problem of thermodynamic stability of shock waves. The conclusions obtained are: the weak shock (including sound waves) is critically stable, the normal plane shock is unstable.