BackgroundHypertension is the leading cause of morbi-moratlity in low, middle as well as high incomes countries. Tunisia is a developing country with a high cardiovascular profile and the prevalence of hypertension has widely increased during the last decades. Thus, we conducted this national survey on hypertension to analyze the profile of the Tunisian hypertensive patient and to assess the level of blood pressure control. MethodsNature HTN is an observational multicentric survey, including hypertensive individuals and consulting their doctors during the period of the study. The primary endpoint of our study was uncontrolled hypertension defined by a systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90mmHg. Our objective is to assess the predictors of uncontrolled hypertension in our population. Results Three hundred twenty one investigators from all the Tunisian governorates participated in the study. We enrolled 25890 patients with a female predominance (Sex ratio 1.21) and an average age 64.4±12.2 year-old. Most of individuals were treated in the public sector (74%), 39.4% of patients were diabetic, 25.8% were obese, 44.6% were overweight and 14% were smokers. Hypertension was controlled in 51.7% of cases if we consider 140/90 as BP target and only in 18.6% if we consider 130/80 as a target. The independents predictors of uncontrolled blood pressure were male sex (OR=1.09, 95%CI [1.02-1.16]), age> 65 year-old (OR=1.07, 95% CI[1.01-1.13], diabetes (OR=1.18, 95% CI [1.11-1.25], Smoking (OR=1.15, 95% CI [1.05-1.25]), Obesity (OR=1.14, 95% CI[1.07-1.21]), management in public sector (OR=1.25, 95% CI [1.16-1.34]) and Heart rate >80bpm (OR=1.59, 95% CI [1.48-1.71]). Contrarily, high educational level (OR=0.9, 95% CI [0.84-0.97], absence of history of coronary disease (OR=0.86, 95% CI [0.8-0.93]), salt restriction (OR=0.48, 95% CI [0.45-0.51]), drug compliance (OR=0.57, 95% CI[0.52-0.61]) and regular physical activity (OR=0.77, 95% CI[0.71-0.84]) are strong predictors of blood pressure control. Conclusion Nature HTN showed a remarkable improvement of blood pressure control amongst Tunisian people. The control remains low in patients with high cardiovascular profile and those treated in the public sector. A national health program based on therapeutic education, regular control and continuous giving much support to the public institutions is needed to decrease the hypertension burden affection rate in our population.