An elastoplastic damage constitutive model based on incremental theory is deduced in strain space.A mesoscopic numerical model to study the progressive failure process and the nonlinear mechanical behavior of heterogeneous rock is established in combination with an elastoplastic damage constitutive for rock mesoscopic element.The failure elements deleting method is used to simulate crack propagation in program.The calculation results achieved by numerical simulation and practical projects application agree well with those of in-situ tests,which illuminates that elastoplastic damage mesoscopic model could reflect local plastic characteristics of fractured rock masses.Three-dimension marble model is more reflect mesoscopic failure than two-dimension model.The failure element deleting method is good at showing explicitly crack propagation.It is proven that the numerical model is right and feasible.The failure elements deleting method solves the difficult problem of FEM to simulate the propagation.The model and method might be valid in practical projects.