Diabetes mellitus (DM) is a common disease affecting over 124 million individuals worldwide. DM is associated with high risk of atherosclerosis and renal, neural, and ocular damage. Increased oxidant stress has been implicated in the pathogenesis of DM. An increase in serum ceruloplasmin (Cp) levels has also been reported in Type 2 DM. Cp permits the incorporation of iron into transferrin (Trf). Trf inhibits iron ion-dependent OHo formation from H2O2. Patients with diabetes have increased levels of plasma lipid peroxidation products. In this study, we evaluated 50 patients with Type 2 DM and 21 clinically healthy subjects. Patients were divided into two groups. Group I included 29 patients without diabetic complications, Group II 21 with diabetic complications. Serum Cp, Trf, C-reactive protein (CRP), triglyceride (TG), cholesterol (Chol), and malondialdehyde (MDA) levels are studied. Serum Cp, CRP, TG, Chol, and MDA levels in diabetic patients were significantly higher than those of controls. Trf levels were significantly lower in diabetic patients than those of the controls. Cp, CRP, HbA1C, and MDA levels in Group II were significantly higher than those of Group I. Our results indicate that oxygen free radicals are formed in DM and can result in diabetic complications and that a prooxidant/oxidant imbalance is involved in the tissue injury in DM and diabetic complications.