Abstract: In order to establish a more advanced statistical damage constitutive model for rocks, this paper contraposed the deficiency that current models have difficulty in reflecting the characteristics that the elastic modulus would vary with the confining pressures under the conditions of triaxial compression test for some certain rocks, analyzed the mechanism of the rock elastic modulus variation from the perspective of the influences of voids of different kinds on the rock deformation characteristics, and on the basis, a method to research the variation of elastic modulus for rocks has been set up according to the relationship between elastic parameters and the number of cracks which are still unclosed inside the rocks. Afterwards, by introducing the statistical damage theory and taking into account the influences of the damage threshold and the deformation characteristics of the residual strength, a new statistical damage constitutive model which is capable of simulating the complete deformation process of rocks would be built, furthermore, a method to determine the parameters in the model has also been provided based on the triaxial compression test curves of rocks. The model this paper proposed is able to manifest the rock elastic modulus variation with the confining pressure while it possesses the advantages of the existing models and is capable of simulating the rock complete deformation process satisfyingly. Finally, through the comparison analysis among the experimental and theoretical curves of the proposed model and another similar model, the rationality and superiority of the proposed model have been demonstrated.