The aim of this study was to examine the structural relationships among sport participation motivation, psychological well-being, life satisfaction and revisit intention with an emphasis on exploring mediating effects of psychological well-being on the relationships among the research variables. Participants, who were members of a fitness center, completed surveys to assess these relationships. Results showed that sport participation motivation leads to psychological well-being and revisit intention, and psychological well-being is a critical factor in influencing life satisfaction and revisit intention. Moreover, the path from sport participation motivation and life satisfaction was fully mediated by psychological well-being, and the path from sport participation motivation and revisit intention was partially mediated by psychological well-being, which underlines the importance of mediation role of psychological well-being. These results imply that fitness managers should manage sport participation motivation and psychological well-being of customers.