The aim of this study was to examine the effect of parentification and self-differentiation on ego-identity. The participants of the study were 538 undergraduate and graduate students from universities in Gwangju and Cheollanam-do. The instruments of the study consisted of FRS-A(Filial Royalty Scoring-Adult), Korean version of Adolescent Ego-Identity Scale, and Korean-translated version of Self-Differentiation Scale. Correlations and a multiple regression analyses were conducted to analyze data. The results of the study were summarized as follows. First, there were significant correlations among parentification, self-differentiation, and ego-identity. Second, higher level of instrumental caregiving and higher level of emotional caregiving predicted higher level of ego-identification, while higher level of unfairness predicted lower level of ego-identity. And high level of cognitive function vs. emotional function, ego-integration, family-projection, and family- regression predicted high level of ego-identity, while high level of emotional severance predicted lower level of ego-identity. The result of the study can be utilized as a source in the field of counseling for young people who have difficulties in developing ego-identity.