OBJECTIVE: Low health literacy has been associated with unfavorable health outcomes. We examined diabetes self- and clinical care measures among adults with diabetes by 3 dimensions of health literacy. DESIGN/SETTING: Questions about health literacy were available for optional use in the 2016 Behavioral Risk Factor Surveillance System. We analyzed 2016 Behavioral Risk Factor Surveillance System data from 4 states and the District of Columbia that had included both the Health Literacy and Diabetes optional modules. PARTICIPANTS: Respondents who participated in the 2016 Behavioral Risk Factor Surveillance System in Alabama, Louisiana, Mississippi, Virginia, and Washington, District of Columbia, and completed both modules (n = 4397). MAIN OUTCOME MEASURES: Health literacy was measured by level of difficulty (easy, difficult) with 3 health literacy tasks: getting health advice or information, understanding health information delivered orally by health professionals, and understanding written health information. Diabetes care measures included physical activity, self-monitoring blood glucose, self-checking feet, hemoglobin A1c testing, professional foot examination, flu vaccination, professional eye examination, dental visits, and diabetes self-management education. RESULTS: Among those with self-reported diabetes, 5.9% found it difficult to get health advice or information, 10.7% found it difficult to understand information health professionals told them, and 12.0% found it difficult to understand written health information. Those who found it difficult to get health advice or information had 44% to 56% lower adjusted odds of A1c testing, professional foot examinations, and dental visits; those who found it difficult to understand written health information had lower odds of self-monitoring glucose and self-checking feet. Difficulty understanding both oral and written health information was associated with never having taken a diabetes self-management class. CONCLUSIONS: Our results suggest that problems with health literacy may be a barrier to good disease management among adults with diabetes and that health care providers should be attentive to the needs of patients with low health literacy, especially for diabetes-specific specialty care.