Background: Oxidized low-density lipoprotein (Ox-(LDL)), a key factor in the development of atherosclerosis, can cause endothelial dysfunction and augment lipid accumulation within the arterial wall. Increased oxidative stress in diabetes contributes to this process. Ox-(LDL) is a highly immunogenic molecule and it is not clear whether anti oxidized (LDL) antibodies (OLAB) are pathogenic or protective in atherosclerosis? The aim of this study was to evaluate Ox-(LDL) and its antibody in type 2 diabetes and healthy subjects.Methods: As a case-control study we evaluated 81 type 2 diabetic patients and 69 non-diabetic healthy persons aged 40 to 65 years. Controls were sex and BMI matched with diabetic patients.Patients with history of cigarette smoking, antioxidant or antihyperlipidemic drugs consumption, coronary heart disease, hypertension, and renal impairment were excluded. We measured serum level of Ox-(LDL) (two monoclonal antibody of Mercodia co.) and OLAB by ELISA. Lipid profile, serum electrolytes, and HbA1c (HPLC) were also determined. Ox-(LDL) and its antibody were compared between diabetic patients and controls and the correlation with lipid profile, HbA1c and BMI were assessed.Results: Serum Ox-(LDL) concentration and Ox-(LDL) to (LDL) ratio were distinctively higher in controls (15.7+-6.9 vs. 11.8+-5.6, P<0.005). Ox-(LDL) concentrations were correlated with (LDL)-C (rs=0.36, P<0.0005) and total cholesterol (rs=0.31, P<0.0005) in both groups but not with age and HbA1c. In diabetic patients, Ox-(LDL) and its antibody were positively correlated (rs=0.26, P<0.05).Obese diabetic patients (BMI > 30) had higher Ox-(LDL) concentrations in comparison with diabetic patients with BMI less than 30.Conclusion: In diabetic patients Ox-(LDL) level is lower than non-diabetics and is correlated with its antibodies. Based on previous findings, we suppose that the pattern of (LDL) oxidation enhances Ox- (LDL) recognition by macrophage via specific legends. This results in low serum Ox-(LDL) concentrations in diabetes.