Abstract: Objective?To estimate the prevalence of hypertension and to identify factors associated with the prevention and control of hypertension in Chinese Yi populations. Methods?A cross-sectional study was conducted in Liangshan Yi Autonomous Prefecture of Sichuan province. Random cluster sampling method was adopted to recruit participants. A total of 1 255 Yi people who were 20 years or older from one urban district and three rural villages participated in this study. Demographic and medical and laboratory data were collected from July to September 2007. The prevalence of hypertension and levels of awareness and control of hypertension were calculated and compared between genders and urban and rural residencies. Results?The age-standardized prevalence of hypertension reached 17.3% in the Chinese Yi populations. Urban residents had a significantly higher level of prevalence of hypertension than that of rural residents (25.9% vs.8.9%, P<0.001). Among the hypertensive patients, 2.8% were aware of their high blood pressure, 26.1% were taking antihypertensive medications, and 8.8% had their blood pressures controlled (＜140/90 mm Hg). Urban residents had significantly higher levels of awareness (35%) and endorsement of treatment (31.1%) than their rural counterparts (13.6% for awareness and 10.6% for treatment, P<0.001). For those living in urban areas, higher prevalence of hypertension was associated with older age, being a woman, having higher annual income (≥￥10 000), overweight/obesity and higher levels of total cholesterol. Older age and high levels of total cholesterol were also found to be associated with increased risk of hypertension in the rural residents. Conclusion?Hypertension is prevalent in Yi populations. The awareness and control of hypertension in Yi populations is poor. Public health interventions are needed.