【摘要】Based on the statistical analysis of a sample composed of 367 enterprise customers from Chinese IT distribution industry,the following theory hypothesis of the changing tendency of customer profit is tested:customer profit increases with relationship phases and is minimum in exploration phase,next minimum in buildup phase,maximum in stability phase,and a complete curve of customer profit likes a reverse‘U’.This paper reports the methodology and results of the experimental research.The certified ‘U’ changing law of customer profit provides hte foundation for putting forward the optimum model of customer relationship life cycle and forecast model of customer lifetime profit,and thereby for finding a solution to some core problems of customer retention.