Abstract：The purpose of this study was to examine the mediating effect of well-being in sport on psychological skills and life adjustment. Two hundred forty-seven male and one hundred-thirteen female athletes from different types of athletic teams of National Taiwan Sport University were participated. In this study Athletic Psychological Skills Inventory (5 subscales), The Well-being in Sport Scale (2 subscales) and WHO Questionnaire on Quality of Life: BREFF-Taiwan Version (4 domains) were used. Hierarchical regression analyses were used to determine the statistical differences. The results of this study indicated that all effects among psychological skills and physical health, social relationship, and environment were full mediated by the sport well-being. However, the effects between psychological skills and psychological domain were partially mediated by sport well-being. Therefore, this study concludes that collegiate athletes, who have better psychological skills would enhance the well-being in sport, and then increase the level of physical health, social relationship and environment. Results of this study provided suggestions for psychological skills, sport well-being and life adjustment, and future relevant research issues are discussed. (Full text)