This study aims at examining how collegiate sport team coaches choose their occupation and build their identity as coach job and providing theoretical frame regarding their identity formation. Grounded theory of Strauss and Corbin has been uses as the methodology of this study. The in-depth interviews and participants observation of 9 collegiate sport team coaches have been conducted for data collection. Result of the analysis are as below : The core category was difficulty of collegiate sport team coach’s life. The formation types of job identity of were overcoming the issue, maintaining the status quo, and avoiding the issue. The coaches realized that the life of coaches and that of athletes are different although they had been athletes themselves in their sport. Social discussion is needed on their unstable social status, unreasonable working condition, and the negative view of them.