Abstract: The concept of generalized potential theory was briefly introduced.Based on the generalized potential theory,the limitation of traditional constitutive theory in expressing the constitutive relation of soils was analyzed,and the advantage of the generalized potential theory in establishing the constitutive model for soils was pointed out.It was shown that the generalized potential theory could break the limitation of the plastic postulate which was the base of the classical elasto-plastic constitutive theory,and the constitutive model based on the generalized potential theory would be used extensively.