Firstly, using the continum damage mechanics theory, the statistical damage constitutive model of rocks under the interaction of confining pressure and axial compression was established based on the randomness of the rock internal cracks and pore distribution. Secondly, the method for determining the model parameters was established by combing the characteristic parameters of rock stress strain curve, which enhanced the adaptability of the model. Finally, the evolutionary path of the rock damage and its macroeconomic performance were investigated, and the model was verified by the test. The results show that the macro mechanical properties of the rock depend on micromechanics response of the internal micro cracks, its damage evolution approach reflects the whole process of rock deformation and failure. In addition the theoretical curve of model and the experimental measured curve has a high degree of matching which verify the rationality of the model.