Abstract: In order to establish an elastoplastic constitutive model for cement-sand-gravel (CSG) material, firstly some samples with cement content of 60 kg/m³ are prepared for the consolidated drained triaxial tests under constant confining pressure, isotropic loading-unloading-reloading tests and loading-unloading-reloading triaxial tests (under consolidated drained condition). The test results depict the stress-strain curves under various confining pressures. Based on the test results and some related researches on CSG material by some experts, the elastic part of the model is put forward, the shear and volume yield surface model is proposed, and by introducing the generalized plasticity theory, an appropriate elastoplastic constitutive model for CSG material is established. The calculated results by the model including 9 parameters are compared with the experimental data of the consolidated drained triaxial tests. It is shown that the proposed model accurately depicts the relationship between stress and strain for CSG material.