In this paper,elastic-plastic constitutive theory has been deeply studied and an elastic-plastic constitutive model is established.The Mande-model skeleton curve is used as equivalent uniaxial stress-strain curve,elastic-plastic model in strain space is used in hardening stage while elastic-plastic model in stress space is used in softening stage.The Huang Kezhi-Zhang Yuangao three parameters model is used as yield surface.The relationship between concrete strength and the parameters of the yield surface is derivated and a practical approach is gave to determine the parameters.This model is developed in ABAQUS,return-mapping algorithm is used as constitutive integration algorithm,it is proved that this model can accurately reflect a variety of constitutive behavior of concrete material through several numerical Simulations.