ABSTRAC This research aims to see whether the implementation of CRM has an effect on increasing customer satisfaction, mark as decreasing churn and increasing effectiveness on marketing activities, in internet business unit. It takes case study on PT. Telkom with focusing in internet ADSL broadband business unit called Telkom ADSl. This Research used qualitative research method with descriptive statistical analysis to describe the impact of CRM implementation to customer satisfaction. Research variables are achieved from initial analysis according to CRM theory using critical success factor method. This research is expected to show the impact of CRM implementation to increasing customer satisfaction and find out it impact to marketing effectiveness and internet service in telecommunication company based on data between 2007 until Mei 2008. The result of this research prove that the implementation of CRM influence, both positive and negative impact, to increasing customer satisfaction. Keyword : churn, critical success factors, CRM implementation, customer satisfaction, customer retention. x + page 100, table 12, picture 27