Religiosity plays a prominent spiritual and social role in adolescents’ lives. Yet, despite its developmental salience, few studies have examined normative changes in religiosity or the implications of these changes for psychological well-being. We explored longitudinal variation in and associations between religiosity, as defined by private regard, centrality, and participation in religious activities, and diverse indicators of well-being including self-esteem, depressive symptoms, positive and negative affect, and both the presence of and search for meaning in life. The participants were two cohorts of Asian American high school students (N = 180; 60 % female) followed for 4 years and living in the southeastern US. Using hierarchical linear modelling and controlling for gender and generational status, results revealed that religious identity (i.e., regard, centrality) did not normatively increase or decrease over time, but participation increased. Religious identity was significantly associated with higher self-esteem, greater positive affect, the presence of meaning in life, and reduced depressive symptoms (for females), and participation was positively associated with positive affect and the presence of meaning. Our results and discussion emphasize the utility of further examining how religion plays a role in health and well-being, particularly among immigrant youth.