: It has been reported that arterial stiffness assessed by pulse wave velocity (PWV) can predict cardiovascular morbidity and mortality. Metabolic syndrome and smoking are independently associated with increased risk of cardiovascular disease. The purpose of this study was to evaluate the effect of smoking on the relationship between metabolic syndrome and arterial stiffness. We retrospectively enrolled 1,530 men on whom brachial-ankle pulse wave velocity (baPWV) measurement had previously been performed as part of health screening at Kosin University Hospital. We found that PWV was positively correlated with the following variables: age (r = 0.391, P < 0.0001), systolic blood pressure (r = 0.438, P < 0.0001), diastolic blood pressure (r = 0.377, P < 0.0001), low-density lipoprotein (LDL) (r = 0.068, P = 0.008) and high-density lipoprotein (HDL) (r = 0.027, P = 0.287), whereas BMI was negatively correlated, although without statistical significance (r = -0.026, P = 0.309). Among current smokers, PWV decreased with increasing BMI (from 1,387.9 to 1,311.6), and increased with increasing HDL (from 1,342.7 to 1,385.4). On the other hand, among never smokers, PWV increased with increasing BMI (from 1,382.3 to 1,458.8), and decreased with increasing HDL (from 1,391.2 to 1,369.7). PWV was inversely associated with BMI and HDL, and these differences are likely due to smoking.