Abstract:On the basis of defining the customer faithful degree, the paper analysed the factors of effecting customer faithful degree. In accordance with the basic rule of target design, a target system has been designed, which can change the abstract, qualitative customer faithful degree into the concrete, quantitative target, then calculate the customer faithful degree. After analyzing the shortcomings of the quantitative ways of customer faithful degree, the paper made further researches on the quantitative way and process of the customer faithful degree.