Background: Older Puerto Ricans belong to two rapidly growing demographic groups known to have high rates of depression: the aging and Hispanic populations. Studies of depression in Puerto Ricans have primarily focused on the impact of demographic factors and health. This study expands previous research, examining the relationships between depression and social stressors, social support, and religiosity, for Puerto Rican primary care patients aged 50 and older. Patients: Participants included 303 Puerto Ricans from six primary care clinics in a northeastern city. Methods: Patients completed in-person interview in Spanish. The Composite International Diagnostic Interview indicated depressive disorders meeting DSM-IV criteria. Bivariate and multivariate relationships between depression and demographics, health, social stress and support, and religiosity were explored. Results: One fifth of participants met DSM-IV criteria for major depression or dysthymia. Participants with the lowest income, more recent migration, and poor subjective health were significantly more likely to be depressed. In addition, rates of depression increased steeply for patients caring for grandchildren and those with personal or family legal problems. Seeing few relatives each month and needing more instrumental, emotional, or financial support were also related to higher rates of depression. Unexpectedly, low objective illness severity correlated with increased depression, whereas religiosity and religious participation had no relationship to depression. Conclusions: The findings presented here indicate the potential for social stressors and inadequate supports to substantially increase the risk of depression in older Puerto Ricans in primary care settings. Further studies should explore incorporating these social risk factors into improved prevention, clinical detection, and culturally sensitive treatment of older depressed Puerto Ricans.