Systemic lupus erythematosus (SLE) is associated with premature atherosclerosis, and an increased susceptibility of plasma lipids and lipoproteins to oxidation could at least in part promote atherogenesis. The objective of this study was to identify the effects of anticardiolipin antibody (aCL) and disease activity on oxidative and antioxidative status in patients with SLE. In this study, patients in SLE/aCL+ group and in SLE disease activity index >3 group had significantly higher thiobarbituric acid reactive substance (TBARS) levels, titers of autoantibodies against oxidized low-density lipoprotein (ox-LDL), and glutathione peroxidase activity than that of healthy controls. However, only TBARS and titers of autoantibodies against ox-LDL but not antioxidant enzyme activities were significantly different between SLE subgroups. Thus, enhanced oxidative status but not corresponding elevated antioxidative status by the presence of aCL and active disease activity make potent antioxidant therapy valuable for these SLE patients in preventing oxidative damage.