Studies on the identity of adolescents based on the perspective of "individual" and "relatedness" are reviewed and discussed. Recent experimental investigations to clarify identity from the above standpoint have focused on the development of identity in women. It has been considered that the concept of "relatedness" in identity is particularity related to the identity of women. However, with the recent recognition that "relatedness" is common to both sexes, conceptual discrimination between "individual" and "relatedness," as well as the relationship between these concepts in development of identity, have become the focus of current discussions. "Relatedness" in adults has been defined from various perspectives. It is considered that "relatedness" in adolescent identity is a factor in promoting the separation of self and others, and in keeping an appropriate distance from others on the basis of trust in the outer world. It is necessary that "individual" and relatedness" in adolescent identity be elaborated and substantiated on the basis of knowledge gained from previous research with adults.