Background: Homeless women experience high rates of mental distress. We sought to determine whether ethnic differences exist in the relationship between the predisposing and enabling domains of the Gelberg-Andersen Behavioral Model for Vulnerable Populations and mental distress. Methods: We selected 821 homeless women in the Los Angeles area using a representative probability sampling design and invited them to participate in face-to-face interviews. The sample was 67% African American, 17% Hispanic, and 16% White. Results: We identified a number of ethnic differences in the correlates of mental distress. Being partnered or married was associated with greater distress among African American and White women, and experiencing competing needs was predictive of distress for African Americans and Hispanics. Conclusion: A variety of factors contribute to mental distress among different ethnic groups of homeless women; these differences should be considered in the development of culturally appropriate services designed to address mental health problems among homeless populations. © 2008 Jacobs Institute of Women's Health.