Background and Objectives Hypertension (HTN) is a major health concern that leads to cardiovascular disease and premature death. Assessing HTN knowledge, attitude, and practice (KAP) is crucial for controlling HTN. This study aimed to determine HTN KAP among hypertensive patients residing in Lebanon. Methods This cross-sectional study involved 342 hypertensive patients. A questionnaire form was used to collect data related to patients’ characteristics. SPSS was used to determine KAP scores, descriptive statistics, and correlations. Results Data from HTN patients was analyzed of whom 98.2% were Lebanese and 51.2% were males. The median age was 59.15 ± 13.55 years old. A proportion of 40.4% had HTN duration for at least 10 years and 67.3% had HTN family history. Patients had fair HTN knowledge and practice, but good attitude toward HTN. Only 45.3% regularly checked their blood pressure. Positive correlations were observed between HTN attitude and each of knowledge and practice. HTN knowledge and attitude were associated with many studied factors, whereas no relationship was found regarding practice. Conclusion Hypertensive patients had fair levels of knowledge and practice, and a good level of attitude concerning their disease. We provided a model for predictors of HTN KAP scores that will allow the development of efficient campaigns related to HTN.