Given that adolescents from migrant families live within at least two cultural contexts (i.e., the heritage and the destination cultures), they generally must negotiate and construct ethnic and national identities. Accordingly, the present three-wave longitudinal study was designed to identify distinct developmental trajectories of ethnic and national identities among adolescents from migrant families ( n = 244, 56.6% female; Mage = 14.90, SDage = 0.84 at Time 1). Multivariate latent class growth analyses indicated that participants could be classified into one of four groups based on their identity profiles: ethnic-oriented identity, national-oriented identity, dual identity, and marginalized identity. Further, social identification with family and classmates was examined as a predictor of memberships in these distinct identity profiles. Results of multinomial logistic regression analysis indicated that greater social identification with family increased the probability of being classified into the ethnic-oriented and dual identity profiles rather than into the marginalized identity profile, whereas greater social identification with classmates increased the likelihood of being classified into either national-oriented or dual identity profiles rather than into the marginalized identity profile. These findings provide novel insights into the roles of families and peers as influential socializing agents during the negotiation of ethnic and national identities among immigrant youth.