Under the four forces of opening up of domestic telecommunication market, breakthroughs in information and communication technology, changes in consumer demand, and supplier¡¦s race for economic efficiency, industry structures have transformed. What used to be three distinct industries of divergent directions of development ¡V network service (computers), telecommunication (telephones) and cable television (television), are interacting. The market is growing rapidly with combined digital flow of the three industries. Broadband internet played a key role in such transformation. ADSL broadband internet service has prospered in recent years. As the internet population approach maturity, the market has changed focus from quantity to quality. There are two major challenges to fixed network internet service providers are: To increase market share by attracting more customers to its service base, and retain customers to minimize loss of customers. Telecommunication service providers attract new customers by offering special prices with gifts, they retain customers by elevating switching cost and long term contracts. But the result of price-cutting competition was erosion of profit margin. Customer loyalty is also swayed by low prices met by competitors. Under such intense competitive environment, service providers are actively developing digital content and making investment in fiber optic broadband to mitigate loss. It is hoped that richer internet content and faster speed broadband can attract more customers and increase customer revenue contribution. The subject of this study are ADSL broadband internet users in the greater Kaohsiung area, the regions surveyed include Kaohsiung County and Kaohsiung City. A questionnaire was used as the data collection tool. The survey was conducted on a convenient sample. Data was analyzed using SPSS statistical software. The influence of customer¡¦s expected future benefits, overall customer satisfaction and marketing strategies on customer retention were investigated. Furthermore, the interaction effects were also reviewed. The results of the study are: I.The most important factor in influencing customer retention is overall customer satisfaction, followed by marketing strategy and customer¡¦s expected future use. Further results are derived from analysis: 1.Overall customer satisfaction, customer¡¦s expected future use and marketing strategy showed significant positive influence on customer retention. 2.The influence of overall customer satisfaction, customer¡¦s expected future use and marketing strategy on customer retention vary in strength. 3.Marketing strategy showed significant positive influence on overall customer satisfaction and customer¡¦s expected future use. 4.With respect to the degree of influence on customer retention, overall customer satisfaction showed greater influence than marketing strategy and customer¡¦s expected future use. II.Customers exhibit high expectations for future use¡C Telecommunication service provider satisfying the following ¡§customer¡¦s expected future use¡¨ will significantly enhance customer retention. 1.Provide value-adding services. 2.Provide more value-adding application content. 3.Offer better prices. 4.Exchange fiber optic with ADSL in the future at free of charge