Antibodies against oxidized low-density lipoproteins (anti-oxLDL antibodies) are involved in the development of atherosclerosis in animal models, but their role in humans is not clear. The aim of this study was to explore the relationship between the presence of anti-oxLDL antibodies and the presence of anti-beta2glycoprotein I (beta2gpI) antibodies, anticardiolipin antibodies and lupus anticoagulant. We also analyzed the relationship between the appearance of anti-oxLDL antibodies and clinical signs of antiphospholipid syndrome. This study included three groups of patients: 27 patients with primary antiphospholipid syndrome, 20 with secondary antiphospholipid syndrome associated with systemic lupus erythematosus and 13 patients with systemic lupus erythematosus. Levels of anti-oxLDL, anticardiolipin and anti-beta2gpI antibodies were detected by ELISA. The presence of lupus anticoagulant was detected by coagulation tests. We found that the presence of anti-oxLDL antibodies was associated with a history of arterial thromboses in patients with secondary antiphospholipid syndrome (chi2 = 8.89, p < 0.01) and in patients with primary antiphospholipid syndrome (chi2 = 4.64, p < 0.05). Also, the appearance of anti-oxLDL antibodies was associated with the presence of anti-beta2gpI antibodies (chi2 = 4.25, p < 0.05), which was not dependent on diagnosis. These preliminary observations have to be confirmed in a larger study.