She received her B.A. from Wellesley College and her Ph.D. from the University of California, Los Angeles. She joined the Cal State L.A. faculty in 1977, and is currently a professor of psychology at Cal State L.A. For the past 15 years, Phinney has been studying ethnic identity and adaptation among adolescents from diverse ethnic and immigrant groups in the United States. She is part of an international team studying adaptation of immigrant adolescents in 12 immigrant-receiving countries.