In order to study the feature of stress deformation of plastic concrete core wall dam,the paper chose the appropriate constitutive model, contact element, construction process and storage process simulation methods, combined the engineering practice and used three-dimensional nonlinear finite element method to calculate the stress deformation of dam.The results show that in the period and storage period,the distribution feature of horizontal and vertical displacement of the dam is consistent with that of general homogeneous earth dam.The major principal stress of dam is compressive stress.The stress increases gradually from surface to internal.The maximum value happens at the bottom of heart near dam core wall.Except less localized tensile stress, the rest of small primary stress are compressive stress.