Coronary Artery Disease is the major cause of mortality and morbidity worldwide. Serum paraoxonase is a high density lipoprotein (HDL)-bound enzyme exhibiting antiatherogenic properties. Oxidative stress plays the major role in the atherosclerotic process. In the pre-sent case control study, serum paraoxonase activity and oxidative stress were monitored in 100 patients with AMI and 50 age and sex matched healthy controls. The levels of total cho-lesterol, triglycerides and low density lipoprotein were significantly (p<0.001) high and the levels of high density lipoprotein were significantly (p<0.001) low in the AMI patients as compared to healthy controls. MDA level was significantly (p<0.001) high and antioxidant activity of PON was significantly low in diabetic (p<0.001) and non-diabetic (p<0.01) AMI patients as compared with controls. Our findings show the increased oxidative stress and decreased paraoxonase antioxidant activity in AMI patients and importance of assessing these markers along with lipid profile in AMI patients.