The current study modeled developmental trajectories of ethnic identity exploration and affirmation and belonging from middle to late adolescence (ages 15-18) and examined how these trajectories varied according to ethnicity, gender, immigrant status, and perceived level of discrimination. The sample consisted of 135 urban low-income Black and Latino adolescents (42% male, 34% Black, 66% Latino). Consistent with developmental theory, individual growth modeling identified an average quadratic trajectory of ethnic identity exploration characterized by decelerating levels of exploration after 10th grade. However, ethnicity and perceived discrimination by peers moderated this pattern. No uniform growth pattern in affirmation was found and Black and Latino adolescents displayed equally high levels of affirmation over time.