The purpose of this study was to examine the relationships among Openness-Closedness of personality, the two phases of self (Connected/Separated), and the Self-Esteem in adolescence. Experience inventory, Connected/Separated-Self scale, and Self-Esteem scale were administered to 479 university students. From the analyses of the data, the following results were found.(1) Open-minded students (OS) had an intense Separated-Self compared with closed-minded students (CS);(2) Only in females, Openness affected positively on the return to balance of Connected/Separated-Self;(3) Whether students were OS or CS made some differences in the relationship between the Connected/Separated-Self and the Self-Esteem. a) Both selves equally tended to influence the fullness and the stability in OS. But in CS the Separated-Self tended to gain predominant influence on the fullness over the Connected-Self. b) When in CS the Connected-Self was weak or the Separated-Self was intense, they were apt to be in maladjustment of human relations. c) In the case of OS who showed intense Connected/Separated-Self, their Self-Esteem was reflected on the conflict of Connected/Separated-Self.