Cholesterol and triglyceride levels have been analyzed in the forensic setting and their values correlated with atherosclerotic lesions found at autopsy and histology. Nevertheless, the results of these investigations have provided diverging information on postmortem molecule stability and postmortem measurement reliability. The aim of this study was to determine triglycerides, total cholesterol, low-density and high-density lipoprotein cholesterol, apolipoprotein B100, and apolipoprotein A-I in antemortem and postmortem serum samples in a series of cases (N = 10, including cardiac and noncardiac deaths) that underwent forensic investigations and had both samples available, measure the same molecules in postmortem serum from femoral blood and pericardial and pleural fluids (N = 39, including cardiac and noncardiac deaths), and evaluate whether different levels of these molecules could be observed in cases characterized by different degrees of coronary artery atherosclerosis (N = 39, including cardiac and noncardiac deaths). Preliminary results indicated that total cholesterol and low-density and high-density lipoprotein cholesterol levels in postmortem serum samples tended to be lower than those in antemortem specimens, whereas triglyceride levels in postmortem serum samples tended to be higher than those in antemortem samples. No relationship could be found between postmortem serum and pericardial fluid levels or between postmortem serum and pleural fluid levels of all tested biomarkers. Lastly, cases characterized by severe coronary artery atherosclerosis revealed higher postmortem serum levels of total cholesterol and apolipoprotein B. Globally considered, these data confirm that femoral blood postmortem serum levels of cholesterol and apolipoproteins may be considered suitable to estimate their antemortem values in forensic cases characterized by coronary artery atherosclerosis.