Abstract:  In order to quantitatively evaluate the relationship between 3G customers and telecom companies,this paper studies the stability of 3G users.By using data mining (DM) and analytic hierarchy process (AHP),a model is proposed for the 3G customer stability evaluation.As an application example,the model is applied to a city’s telecom company.By using the proposed method,it grades the current 3G users of the company and obtains the stability distribution.This presents the important information for the company.Thus,the model strongly supports the relationship maintenance of 3G customer and the corresponding service provision.