The relationship between adolescent suicide attempts and death by suicide and psychosocial functioning of peers remains poorly understood, especially in the myriad ways that these suicidal behaviors might impact friends. This study explored the relationship between peer suicidal behavior and adolescent risk behavior using a large, nationally representative sample of adolescents (N = 5852). Results indicate that youth exposed to peer suicidal behavior are significantly more likely to have their own suicidal ideation and attempts, and to smoke cigarettes and marijuana, binge drink, be involved in a serious physical fight, and have inflicted injuries that require medical attention. These results highlight the need for professionals to be aware of these risks in friends of those who have attempted or died by suicide. Assessment and intervention for peers is appropriate and required for this at-risk group.