Background: Hypertension remains a major health problem, causing high mortality and morbidity all over the world. It is considered a major risk factor for both cerebrovascular accidents (CVAs) and coronary artery disease (CAD). Objectives: To assess the level of knowledge of hypertensive patients in Makkah City.        Methods: A cross-sectional analytical questionnaire based study among hypertensive patients of Makkah City. Results: The mean age was 45 years, ranged from 35 to 70 and 63.33% were females and 36.67% were male respondents. The majority of them had college degree and were employed. Most of the respondents had good knowledge about hypertension, risks and treatments. Neither age nor gender showed association with the levels of knowledge in included subjects but education was significantly associated with high levels of knowledge. Conclusion: The general knowledge score was good with high knowledge about risks and treatments. Doctors were not informative to patients about hypertension. Also, education significantly impacts the knowledge of population about hypertension.