This paper presents the stress-strain, volumetric strain characteristics of the Pocheon weathered residual granite soil with variation of the initial water content under drained conditions. A series of consolidated drained triaxial compression tests and isotropic compression tests with various initial water content on specimens were performed. All material parameters of Lade's double work hardening model were determined by using the results of tests. Most aspects of the soil behavior measured in the triaxial compression tests were reproduced with good accuracy by the constitutive model. Therefore double work hardening model has been shown to be applicable to weathered residual granite soil.