This longitudinal study examined the relation between puberty, as measured by both pubertal status and timing, and adjustment problems, as measured by externalized hostile feelings and internalized distress symptoms, among adolescent males in grades 7 through 10. The results showed that boys who were physically more developed in grade 7, compared with their less physically developed peers, manifested more externalized hostile feelings and internalized distress symptoms in grades 8 through 10. Pubertal timing was significantly related to both internalized distress and externalized hostile feelings. This relation remained statistically significant, even after controlling for grade 7 maladjustment symptoms and concurrent stressful life events. Several significant interaction effects emerged between pubertal timing and concurrent stressful life events. The significant long-term effect of the pubertal transition, independent of stressful life experiences and symptom continuity, suggests that the past undifferentiated view of the favorable influence of early maturation on males needs to be modified.