Objectives. To assess the relationship between nonalcoholic fatty liver disease (NAFLD) and arterial stiffness according to metabolic syndrome(MetS) in non-diabetic, non-hypertensive individuals. Methods. Hepatic ultrasound and brachial–ankle pulse wave velocity(baPWV) were investigated among 4,467 individuals (3,444 men, mean age 52짹11.4 years) from Kangbuk Samsung Health Promotion Center between 2008 and 2009. The subjects were classified into normal PWV and increased PWV(���1366cm/s) groups, and divided into 2 groups (non-NAFLD vs. NAFLD groups) and 3 groups (non-, mild, and moderate to severe NAFLD groups), respectively. Results. The overall prevalence of NAFLD based on ultrasound findings was 37.3% and NAFLD group had higher level of baPWV (controls vs. NAFLD, 1363짹210.3 cm/sec vs. 1388짹235.9 cm/sec, p<0.001). In the multivariate regression analysis, NAFLD had an independent association with abnormal baPWV irrespective of multiple covariates (OR[95%CI] 1.24[1.05-1.46]); the analysis according to degree of NAFLD also showed similar results(1.21[1.02-1.43] in mild NAFLD, 1.62[1.12-2.36] in moderate to severe NAFLD). Subgroup analyses revealed that there was a significant association between NAFLD and baPWV only in individuals without MetS (1.27[1.07-1.51]). The multivariate linear regression models in total population and individuals without MetS also showed a significant association between NAFLD and absolute values of baPWV (standard 棺=0.03 p=0.043 in total population; standard 棺=0.041, p=0.008 in individuals without MetS). Conclusions. Our results indicate that the presence and the degree of NAFLD are associated with arterial stiffness in non-hypertensive, non-diabetic individuals, especially in individuals without metabolic syndrome, suggesting that NAFLD could be a mediator of arterial stiffness, independent of MetS.