Discretization of continuous attributes is an important link that the rough set theory applied to the practical issues,but there is a larger choice of numerical uncertainty of the general method of discretization.In this paper,the posture difference composed by numerical difference studys the difference problem,and the results applied to the process of discretization of continuous attributes,forming a new method of discretization of continuous attributes based on the numerical difference analysis,resolving the issue of its uncertain,and finally giving a examples to verify.