A vast amount of evidence during the past decade, has confirmed that lead is associated with lipid and lipoprotein abnormalities which play a major role in the pathogenesis and progression of atherosclerosis and cardiovascular diseases. This study aimed: to investigate the relationship between chronic occupational lead exposure, lipid profile, and serum PON1 activity as one of the mechanisms of atherosclerosis. Male workers (n=100) in lead battery manufactory were recruited for this study. They were compared with 100 male age matched non-lead workers. Serum lipid profile and paraoxonase activity were done to their samples. Serum Lead was determined vsing atomic absorption spectroscopy. There was significant differences regarding triglycerides, total cholesterol, and HDL-c (p=0.01, 0.05 and 0.04,  respectively) between both groups. A cumulative effect of blood lead on lipid profile was significantly detected. Multiple linear regression analysis showed that blood lead level was the only negative significant predictors  to serum paraoxonase activity (p=0.03) in lead workers. lead exposure is associated with increased triglycerides, total cholesterol and LDL-c and decrease HDL-c. Because of the protective role of PON1 in the development of atherosclerosis, decrease in serum PON1 activity due to lead exposure may render individuals more susceptible to atherosclerosis.