Abstract: Within the framework of continuum mechanics and immiscible mixture theory, and by assuming that there is no relative motion between the components, an elastic-plastic constitutive model involving damage evolution for fluid-saturated porous solid is proposed. The porosity evolution is established on the conventional equipressure experiments and the effect of porosity on the yield function is considered in the new constitutive relations. By using the B-W-N-B effective stress rule, the blast waves in the fully water-saturated porous tuff are numerically simulated and the results are in good agreement with experiments, demonstrating that the model proposed in this paper is capable of predicting blast waves in water-saturated porous rocks.