Objective: To evaluate the age-specific, sex-specific, and race-specific prevalence of hypertension among South African adults using a nationally representative dataset. Methods: Data from the 59 227 adults (ages 18 and older) who participated in the 2010 South African General Household Survey (GHS) were analyzed using age-adjusted logistic regression models and direct age standardization. Results: The weighted prevalence of self-reported diagnosis of hypertension by a health professional was 10.4%. The prevalence of hypertension increased significantly with age for both men and women. For black African, coloured, and Indian/Asian populations, the prevalence of hypertension in women was about twice the prevalence for men, with the gap narrowing for older adults. For white South Africans, the age-standardized rates were not significantly different by sex. The highest age-standardized diagnosed hypertension rates were for coloured women and black African women; the lowest age-standardized rates were for black African men and Indian/Asian men. In total, 94% of those reporting a diagnosis of hypertension reported taking antihypertensive medications. Conclusion: There is a significant burden from hypertension in South Africa, especially as the under-diagnosis of hypertension may mean that the GHS underestimates the true rate of high blood pressure in the population.