Assessing hypertension prevalence, treatment and control by sociodemographic factors in Iran. We analyzed data from the 2006 National Surveillance of Risk Factors for Noncommunicable Diseases of Iran with a population-based sample of almost 30,000 people aged 15-64 years. Multiple logistic regression models were used to explore differences in hypertension prevalence, treatment and control, adjusting for sociodemographic factors, comorbidities and behavioral factors. Hypertension prevalence was 17.37%. Among hypertensive patients, 33.35% were under treatment, and, among treated people, 35.10% had hypertension controlled. In multiple-regression analysis, age, male sex, low level of education, Kurd ethnicity, overweight and obesity, diabetes mellitus, lower level of physical activity and high-Human Development Index provinces were independently associated with higher prevalence of hypertension. Income and living in rural or urban area were not related to hypertension prevalence. Treatment rates were lower in men, younger people and people of low education and low income, but there were no treatment rate disparities connected to living area, ethnicity and provinces (by Human Development Index). In addition, diabetic patients, obese people and past daily smokers had higher treatment rates. Lower control rates were independently associated with male sex, higher age and lower education, but not with other variables. In Iran, there is comparatively higher prevalence of hypertension among people of Kurdish ethnicity, people of low education and in high-Human Development Index provinces; a lower treatment rate among men, younger people, people of low education and low income; and a lower control rate among men and people of low education. These disparities should be addressed by researchers and health policy makers.