Neighborhood social cohesion (NSC) may contribute to understanding how neighborhood contexts influence the physical and mental health of residents.We examined the relation of NSC to self-rated mental and physical health and evaluated the mediating role of NSC on relations between neighborhood socioeconomic status, ethnic composition, and health.A sample of 3,098 Hispanic and non-Hispanic residents within 597 census tracts in metropolitan Phoenix, Arizona rated their health, psychological distress, and their perceptions of NSC. Census tract estimates provided neighborhood contextual measures.Neighborhood social cohesion was significantly related to better physical and mental health. Both individually rated NSC and neighborhood-level NSC mediated relations between neighborhood contexts and health outcomes. Substantive findings were consistent across Hispanic and non-Hispanic residents.The findings have implications for improving ethnic and socioeconomic disparities in physical and mental health through attention to social cohesion among neighborhood residents.