Firstly,a dynamic mechanism affected by four effects,which are the detainment excitation effect,the natural bleeding effect and the word-of-mouth effect is analyzed,and the evolution route of customer retention rate in customer detainment cycle is obtained;secondly,four coefficients influencing customer retention rate are proposed,which describe the effects above,including detainment excitation coefficient,competition counterattack coefficient,natural attenuation quotient and word-of-mouth influence coefficient;thirdly,customer detainment cycle is obtained based on the evolution route of customer retention rate,and customer detainment value models are established under three circumstances depending on whether the competition counterattack effect exists or not;finally,a customer detainment cost evaluation model based on customer detainment value and customer detainment cost is established,meanwhile,a customer detainment ranking model based on the importance of detainment is built.The experiments results suggest that the customer churn detainment method put forward in this paper is feasible and very efficient.