The purpose of this research are to identify causalities among flow, addiction, customer satisfaction and customer loyalty in online games and to identify the factors by which flow and addiction are influenced. Many previous researches in the area of online games have been carried out about addiction by psychologist and about the development of related technologies by scientists. There are only a few studies about the customer satisfaction from the online business perspective. However, this research is different from the previous ones in the sense that both flow and addiction are considered in the study of the relationship between customer satisfaction/loyalty and flow/addiction in the area of online games.Online game players were surveyed and the data were statistically analyzed empirically. Empirical results indicate that six independent variables such as site design, information, operator, feedback, motivation and time have impacts on the flow. On the other hand a person's impulsiveness, motivation, and average time spent are positively related with addiction. In addition, with the analysis of indirect effect among time, flow and addiction, time spent is more closely related with addiction than flow, which probably means that on average addicted people spend more time on online games than the people in flow. Conclusively, customer satisfaction and loyalty are positively related not with the addiction but with the flow. Besides, customer loyalty is significantly influenced by the flow and the customer satisfaction. This indicates that companies in the online game industry have to develop a strategy for the flow which is more socially and ethically allowable than the addiction.