The increasing importance of genomic information in clinical care heightens the need to examine how individuals understand, value, and communicate about this information. Based on a conceptual framework of genomics-related health literacy, we examined whether health literacy was related to knowledge, self-efficacy, and perceived importance of genetics and family health history (FHH) and communication about FHH in a medically underserved population. The analytic sample was composed of 624 patients at a primary care clinic in a large urban hospital. About half of the participants (47%) had limited health literacy; 55% had no education beyond high school, and 58% were Black. In multivariable models, limited health literacy was associated with lower genetic knowledge (β = -0.55, SE = 0.10, p < .0001), lower awareness of FHH (odds ratio [OR] = 0.50, 95% confidence interval [CI; 0.28, 0.90], p = .020), and greater perceived importance of genetic information (OR = 1.95, 95% CI [1.27, 3.00], p = .0022) but lower perceived importance of FHH information (OR = 0.47, 95% CI [0.26, 0.86], p = .013) and more frequent communication with a doctor about FHH (OR = 2.02, 95% CI [1.27, 3.23], p = .0032). The findings highlight the importance of considering domains of genomics-related health literacy (e.g., knowledge, oral literacy) in developing educational strategies for genomic information. Health literacy research is essential to avoid increasing disparities in information and health outcomes as genomic information reaches more patients.