Often cited as a developmental and cultural resource, religion has been widely studied. However, fewer studies have explored the relationship between nonorganizational religious involvement (NRI) and psychosocial well-being among Black youth or within ethnic groups of Black youth. This study examined this relationship among 1,170 African American and Caribbean Black youth who participated in the National Survey of American Life–Adolescent Supplement study. Moderated hierarchical regression results showed significant main effects of NRI on life satisfaction, self-esteem, coping, and depressive symptoms after accounting for study covariates (i.e., age, gender, family income, denomination, ethnicity, religious service attendance, and religious socialization). No significant interaction effects were observed between NRI and ethnicity on any of the psychosocial well-being outcomes. Results illuminate a promotive effect of NRI in this sample. Though no significant ethnicity and religiosity interaction effects were observed, findings suggest the importance of NRI as a key intervention target to support better psychosocial well-being among Black youth, in an effort to promote overall youth development.