This paper examined what influence romantic relations and romantic breakups have on the domain of self-concept. We predicted that individuals in romantic relations (romantically involved group) would show many positive traits and feelings.compared to individuals who experienced a romantic breakup in the past one year (broken heart group) and individuals who had no romantic involvement in the past one year (non-romantic group). The 347 undergraduate students completed the "Who am I?" test and a questionnaire related to romantic relationships. The following three results were found. First, romantically involved men had more descriptions of activity compared to broken heart men, and greater descriptions involving negative traits were found for broken heart men. Second, compared to romantically involved men and non-romantic men, broken heart men had many descriptions about psychological self. Third, the number of descriptions of psychological self among the broken heart group depended on not the romantic relation traits during courtship, but had a positive relation with the number of coping activities during the breakup period. The self-descriptions for women did not differ among three groups. We discussed the influence of romantic relationship and romantic breakup on various self-concept domains and gender difference.