Religiousness has been associated with decreased risk of suicidal ideation, suicide attempts, and completed suicide, but the mechanisms underlying these associations are not well characterized. The present study examined the roles of religious beliefs and social support in that relation. A survey measuring religiousness, social support, suicidal ideation, and suicide attempts was administered to 454 undergraduate students. Involvement in public, but not private, religious practices was associated with lower levels of both suicidal ideation and history of suicide attempts. Social support mediated these relations but religious beliefs did not. Results highlight the importance of social support provided by religious communities.