Objective This study examined the relationship between social support and suicidality among youth from a public health perspective by using (1) a socioecological framework and (2) an intersectional approach to social identity. Methods Secondary analysis of cross-sectional survey data (N = 5058) involved means comparisons and a series of standard and hierarchical regression analyses. Results Youth with intersecting marginalized identities (i.e., females and racial and sexual minority youth) were significantly more likely to report higher suicidality scores. Social support at the family, school, and community levels was significantly associated with lower suicidality scores, and the combination of family and school support was associated with the lowest suicidality scores. Finally, family support significantly reduced the relationship between intersecting marginalized identities and suicidality. Conclusions Findings highlight the importance of protective factors in every context in which youth live, learn, and play. Measuring and reporting social identities as well as their intersections add to our understanding of both risk and prevention.