The purpose of this study was to examine the relationships among recreation involvement, place dependence, place identity and environmentally responsible behavior as well as clarified the mediating effects of place dependence and place identity in their relationships. A total of 401 valid questionnaires were collected from a sample of SCUBA divers in Taiwan. The results showed that recreation involvement had positive effect on place dependence, place identity and environmentally responsible behavior. In turn, place dependence had positive effect on place identity. Lastly place dependence and place identity had positive effect on environmentally responsible behavior. Moreover, place dependence and place identity, as an intermediate variable, had a significant influence on the relationship between recreation involvement and environmentally responsible behavior.