This study examined the moderation effects of family cohesion and social self-concept on the well-established relation between depression and suicide ideation. Participants were 3,634 primary and 2,706 secondary school students. Based on hierarchical regression analyses, results confirmed the hypothesis that family cohesion and social self-concept were significant moderators for children and adolescents. Specifically, better family support and peer relationships weakened the relation between depression and suicide ideation. Further analysis showed that the moderation effect of social self-concept was less obvious among adolescents. The study introduced another approach for future research that includes other potential variables as moderators in the relation between depression and suicide ideation.