Background: Previous studies have shown that minority populations have low rates of documented advance directives and express preferences for more life-prolonging interventions at the end of life. We sought to determine the impact of Latino ethnicity on patients' self-report of having an advance directive discussion and having a completed advance directive in the medical record at an index hospitalization for serious medical illness. Methods: This was a prospective observational cohort study of 458 adults admitted to the general medical services of a safety net hospital, an academic medical center, and a Veterans' Affairs (VA) hospital. Patients were asked if they had discussed advance directives, and we reviewed medical records for documented advance directives. Results: Overall, 45% of patients reported having had a discussion about advance directives (29% of Latinos compared with 54% of Caucasians, p=0.0002) and 24% of patients had a completed advance directive in their medical record (25% Latinos and 26% of Caucasians, p=not significant [ns]). Using logistic regression modeling and adjusting for socioeconomic status (SES), education level, and language spoken, Latinos (odds ratio [OR] 0.42, confidence interval [CI] 0.24-0.75) were less likely to report having advance directive discussions compared with Caucasians (referent). However, modeling of a completed advance directive in the medical record showed no significant difference between Latinos (OR 1.44, CI 0.73-2.85) and Caucasians (referent). Conclusions: The unexpected discrepancy we found highlights the need for more effective communication in advance care planning that includes education that is culturally sensitive and accessible to persons with low health literacy.