Introduction: Essentially a pump, the heart is a muscle made up of four chambers separated by valves and divided into two valves. Each half contains one chamber and first half is called an atrium and the other half is called a ventricle. The atria collect blood, and the ventricles contract to push blood out of the heart. There are many Disease coming under the cardiovascular disorder Hypertension, myocardial infarction, coronary artery disease, rheumatic heart disease, arrhythmias, stroke and congenital cardiovascular defects. IN recent year, Non- Communicable Disease (NCDs) are also one of the biggest threats to humanity by causing significant mortality and morbidity worldwide including Low and Middle income countries (LMICs). Aim Of The Study: To assess the level of knowledge regarding lifestyle modifications . Methodology: The Cross sectional research is conducted using group of Cardiac patient in NMCH Jamuhar, Sasaram, Rohtas , Bihar from 6/02/2023 to 11/02/2023. A self structured questionnaire tool was used to assess the knowledge regarding lifestyle modification among 60 Cardiac Patients adopting Convenient sampling technique. Results: There are 60 cardiac patients sample, (23.33%) patient have good knowledge, (53.34%) patient have average knowledge, and ( 23.33%) patient have poor knowledge. This shows that these variables had influenced knowledge in this study. No association was found. Conclusion: The present study was aimed at assessing the knowledge regarding lifestyle modifications among the cardiac patients in NMCH, Jamuhar, Sasaram, Rohtas (Bihar)’’.The relevant data was collected statistically based on objectives of the study. There are 60 cardiac patients sample, (23.33%) patient have good knowledge, (53.34%) patient have average knowledge, and ( 23.33%) patient have poor knowledge. This shows that these variables had influenced knowledge in this study.