The increased deposition of visceral fat in the postmenopause period increases the production of inflammatory cytokines and the release of tumor necrosis factor- α (TNF-α), interleukin-6 (IL-6), and decrease in IL-10. This study investigated the relationship between inflammatory biomarkers and metabolic syndrome (MS) in postmenopausal women considering different diagnostic criteria. We conducted a cross-sectional observational study based on STROBE. Data were collected regarding the diagnostic criteria for MS (International Diabetes Federation; NCEP (International Diabetes Federation (IDF), National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP-III), and Harmonized criteria), body composition, comorbidities, time without menstruation, values of IL-6, IL-10, and TNF-α. ANOVA, Kruskal–Wallis, Levene tests, ROC, and odds ratio were performed to analyze the data. The results showed no significant difference between the methods and no interaction between the method and the presence of MS. However, for the values of WC, body fat percentage, TNF-α, and IL-10/TNF-α ratio, a significant effect of MS was observed. In subjects with MS, lower values of body fat percentage and TNF-α and higher values of the IL-10/TNF-α ratio were also observed. The higher IL-10/TNF-α ratio in the MS group is related to the greater anti-inflationary action of IL-10. The IL-10/TNF-α ratio showed significant accuracy to discriminate patients with MS according to the NCEP-ATP III criteria.