Abstract: Self-expansion model proposes that people have the motivation to seek to expand the self (i.e. people seek to enhance their potential self-efficacy by expanding themselves). Self-expansion model emphasizes that self-expansion motivation is a central human motivation. One way in which people expand themselves is through including others in themselves, to some extent, the other’s resources, perspectives and identities. Self-expansion model is a conceptual framework that seems as a platform for researching relationships and relationship-linked phenomena. The ideas in self-expansion model renew the view of “similarity-attraction effect”, “contact hypothesis”, and related perspectives about close relationships and intergroup relationships. Furthermore, it is helpful to some actual activities such as smoking abstinence. However, self-expansion model itself has not yet been mature. In the future we must take advantage of more other psychological theories for deeper exploration about the model. Meanwhile, we should apply it to the applied fields.

Key words: self-expansion, self-efficacy, close relationship, relationship satisfaction