Background: Nonalcoholic fatty liver disease (NAFLD) has been reported to be the hepatic manifestation of the metabolic syndrome (MetS). However, it has not been studied for the unique characteristics of the two conditions, separately. The present study was aimed to evaluate how differently the MetS and ultrasonography-guided NAFLD were associated with carotid atherosclerosis, vascular risk factors, and inflammatory markers .Methods:Two hundred and sixteen hospital workers were examined for the MetS as guided by Adult Treatment Panel (ATP–III), NAFLD ultrasonographically, and carotid intima-media thickness (IMT). Anthropometric examination, homeostasis model assessment (HOMA) for insulin resistance, and serological markers were also analyzed. All the subjects were categorized into three groups, control, NAFLD, and the MetS. Results: Carotid IMT was thickest and the plaque was most prevalent in the MetS (Figure). Obesity indexes and lipid profiles in NAFLD were significantly higher than the control, and the changes of oxidative stress and inflammatory markers like bilirubin, uric acid, C-reactive protein, and leukocyte counts in the MetS showed significant differences from NAFLD. Logistic regression analysis showed that the presence of carotid plaque was significantly associated with the MetS (OR; 5.36 95% CI; 2.00-14.30, P = 0.001). The association was significant even after potential confounders including VFT, uric acid, and leukocyte counts were adjusted further. Conclusion: NAFLD itself might be a pivotal point as for the MetS and atherosclerosis. Increased obesity indexes and lipid profiles (in NAFLD) might have proatherogenic potential and superimposed inflammatory and oxidative stresses (in the MetS) can directly induce atherosclerotic processes.