Oxidative stress conditions associated with atherosclerosis leads to oxidative modification of low-density lipoprotein (LDL). The body’s capabilities to inhibit LDL oxidation and to remove or neutralize the atherogenic oxidized LDL (ox-LDL) are limited. When the LDL cholesterol level increases in the blood, it leads to dangerous consequences like atherosclerosis, leading to myocardial infarction. The major effect of an antioxidant in the LDL environment is to prevent the formation of ox-LDL (during atherogenesis. Strategies to reduce LDL oxidation and prevent atherogenesis can involve the enrichment of arterial cells with potent antioxidants that can prevent oxidative damage to the arterial wall. The objective of this study is to evaluate the effect of l-arginine on serum lipid and cholesterol levels in the patients of acute myocardial infarction (AMI). The study consisted of 70 AMI patients and 60 healthy individuals (serving as control) age 55–65 years. Serum levels of total cholesterol, high density lipoprotein (HDL), LDL and Triglycerides were determined on day 1 and day 15 of l-arginine administration (oral dose 3 g/day). The total cholesterol/HDL and the LDL/HDL ratio were calculated and compared. As per the observations, l-arginine administration was found to improve the lipid profile of the subjects. Hence it could be used as an adjuvant therapy for AMI and as a preventive measure for the onset of the disease in the healthy elderly also.