Abstract：Based on the testing data of the triaxial consolidation tests on the upstream main rockfill materials used to build the dam in Nuozhadu hydropower station under different stress paths，the shear strength and stress-strain properties are studied and the stress-strain parameters of the rockfill materials are obtained. The Nuozhadu hydropower station is located in Lancang River，Yunnan Province. Several conclusions are drawn after an analysis of the properties of the stress-strain under the special stress paths that the stress-strain properties are controlled by the stress paths and the rockfill materials and the actual stress paths are consistent with the assumed stress paths in the triaxial consolidation test. It is found that there is a great difference for the rockfill materials¢ deformation moduli under the different stress states. According to the data of the triaxial consolidation tests，the strength parameters and the deformation moduli of the rockfill materials under different stress paths with a constant stress ratio are figured out. The stress state is one of the main influential factors for the rockfill materials strength and it has close relationship with strength. The relationships among the stress state，the cohesion and the frication-angle，strength parameters are discussed. All these researches are significant for establishing the mechanical constitutive relations of the dam and analyzing the dam¢s stability in Nuozhadu hydropower station
