Han is the largest nationality and Zhuang is the largest minority among the 56 nationalities in China. Geographically and linguistically, Zhuang can be classified into 43 ethnic subgroups, with the Hei Yi Zhuang Chinese, who live in Napo County bordering northeast Vietnam and comprise a population of 51,655, having the most conservative culture and customs (Hei Yi means "black-clothing" and the Hei Yi Zhuang revere and wear the color black). The determinants of hypertension and its risk factors in this population have not been well-defined. To obtain some of this information, a cross-sectional study of hypertension was carried out in 1,166 Hei Yi Zhuang Chinese (aged 7-84; mean, 44.00+/-17.54 years) and 1,018 Han Chinese controls (42.95+/-17.11; range, 6-89 years) in the same area. Information on demographic characteristics, health-related behaviors and lifestyle factors was collected by questionnaire. The overall prevalence rates of hypertension and isolated systolic hypertension in Hei Yi Zhuang were higher than those in Han (23.2% vs. 16.0% and 11.5% vs. 3.7%; p<0.001 for each). The levels of systolic blood pressure and pulse pressure in Hei Yi Zhuang were also higher than those in Han (p<0.001 for each). The prevalence of hypertension was positively correlated with triglycerides, male gender, and age in Hei Yi Zhuang, whereas it was positively correlated with total cholesterol, male gender, age, and alcohol consumption in Han. The rates of awareness, treatment and control in Hei Yi Zhuang were lower than those in Han (8.5% vs. 20.9%, 4.4% vs. 15.3%, and 1.9% vs. 10.4%; p<0.001 for each), which may have been due to unique geographical characteristics, unwholesome lifestyles, greater sodium intake, lower education levels, and genetic risk factors in the former group.