Aim. To assess possible differences in serum cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides, arteriosclerosis index, established risk factor (ERF) of arteriosclerosis, and 10-year risk for coronary disease according to the Adult Treatment Panel III (ATP-III) between veterans with combat-related posttraumatic stress disorder (PTSD) and a control group consisting of patients with major depressive disorder. Method. We determined serum cholesterol, LDL-C, HDL-C, and triglycerides in the patients with PTSD (n=103) and patients with major depressive disorder (n=92), using the enzyme-assay method. AI, ERF, and ATP-III were calculated from cholesterol, LDL-C, and HDL-C levels. The groups were matched in age and body mass index (BMI). Patients with major depressive disorder were chosen as a control group because they do not have changes in serum lipids. Results. Patients with combat-related PTSD had higher cholesterol (6.21.1 mmol/L vs 5.30.9 mmol/L; p0.001), LDL-C (3.90.7 mmol/L vs 3.51.0 mmol/L; p=0.005), and triglycerides (2.92.3 mmol/L vs 1.50.5 mmol/L; p0.001), and lower HDL-C (1.00.3 mmol/L vs 1.30.2 mmol/L; p0.001) than the control group. Arteriosclerosis index (4.21.2 vs 3.71.7; p =0.050), ERF (6.41.9 vs 5.52.4; p=0.010), and ATP-III (12.13.3 vs 10.23.8; p0.001) were higher in PTSD than in the control group. Conclusion. Elevated concentrations of serum lipids are associated with combat-related PTSD. This may imply that patients with combat-related PTSD are under a higher risk for arteriosclerosis.