Systemic lupus erythematosus (SLE) is associated with premature atherothrombotic complications. Hyperhomocysteinemia is considered a cardiovascular risk factor. Increased vascular stiffness may increase cardiovascular mortality. Pulse wave velocity (PWV) is a noninvasive method of analyzing vascular stiffness in the assessment of atherosclerosis. The objective of this study was to identify the relationship between plasma homocysteine levels and brachial-ankle pulse wave velocity (baPWV) measurement in SLE. Plasma homocysteine, baPWV, ankle-brachial index, blood pressure, C3, C4, anticardiolipin antibody (aCL), and anti-double-stranded DNA antibodies were determined in a total of 58 female patients with SLE. The control group comprised 32 age-matched healthy females. In addition, all patients were further classified into subgroups according to the presence of aCL (SLE/aCL+, n=27 vs SLE/aCL-, n=31) to determine the effect of aCL on the tested variables. The mean values for plasma homocysteine and baPWV were 13.19 mumol/l and 1,482 cm/s, respectively. Plasma homocysteine levels were significantly elevated in SLE patients when compared with the healthy controls. SLE patients with aCL had a significantly higher plasma homocysteine level than those without aCL. A significant positive correlation between plasma homocysteine and baPWV was found in patients with SLE (r=0.335, P=0.028, n=58). Plasma homocysteine also significantly correlated with right baPWV in all SLE patients (r=0.371, P=0.014, n=58) and in the SLE/aCL+ group (r=0.523, P=0.031, n=27). These findings indicate a possible link between plasma homocysteine and baPWV in SLE. In conclusion, SLE patients had an increased level of plasma homocysteine, and this phenomenon appeared to be related to vascular stiffness.