The samples of 18Cr-10Ni stainless steel containing a submicrocrystalline austenitic phase were processed by deformation-heat treatment. The investigations show that the internal friction and yield strength values of these samples are higher than in the steel with a coarse-grained austenitic structure, by a factor of 4 and of 5, respectively. The effect revealed is connected with both the small grain size and the non-equilibrium state of grain boundaries in the submicrocrystalline austenitic phase of the samples.