This paper presents an elastoplastic constitutive model unifying thermo-hydro-mechanical modeling for unsaturated soils.It is based on existing hydro-mechanical models of unsaturated soils and experimental evidence of temperature effects on soils.The average soil skeleton stress

modified suction and temperature are selected as stress variables

while the soil skeleton strain

saturation and entropy are selected as strain variables.LY and TY yield surfaces and the hardening laws are adopted for simulating temperature effects on volume change.The predictions are performed on the test results in literature including the isotropic compression tests and triaxial shear tests under different net stresses

suctions and temperatures.The comparisons between measured and predicted results indicate that the proposed model can quantitatively predict the volume change behaviour of unsaturated soils under thermo-hydro-mechanical coupling conditions.