The purpose of this study was to describe the team competency and to present theoretical suggestions for the establishing processes of team competency. Previous studies have delineated team competency in terms of “task accomplishment” and “relationship maintenance.” Recent studies argued the necessity to incorporate “environment adaptation” as a team competency. This study focuses on three levels of team competency (task accomplishment and relationship maintenance, role enlargement, and adaptability for environment change)and examines the relationships of the degrees of team consciousness before and after team activities with the level of team competency. Questionnaires were administered to 89 business persons. The results showed that (1)teams with higher competency in task accomplishment and relationship maintenance tended to acquire more success lessons based on consciousness after the task accomplishment, and (2)this tendency was also shown for the team with higher competency in role enlargement. Furthermore, teams with higher adaptability were (3)more conscious of the learning goal before task activities as well as about lessons after task accomplishment. Based on these findings, we propose the theoretical suggestions for the processes on the establishment of team competency.