Objectives: A body shape index (ABSI) and body roundness index (BRI) were reported to predict diabetes and hypertension in general population, but their validity was regularly questioned. The aim of this study was to evaluate whether ABSI and BRI are the best anthropometric indices to reflect metabolic syndrome (MetS), insulin resistance (IR), and inflammatory factors in obese and overweight Chinese adults. Methods: Cross-sectional data on sociodemographic, lifestyle, anthropometric indices, clinical characteristics, and biochemical measurements were collected for 1442 Chinese obese and overweight adults. Logistic regression analysis examined the associations between anthropometric indices with incidences of MetS and IR in both sexes. Furthermore, the correlation between anthropometric indices and inflammatory factors was assessed. Results: Multivariate regression analysis depicting BRI and waist circumference (WC) were associated significantly with MetS and IR. BRI had the highest odds ratios (ORs) for IR and WC had the highest ORs for MetS in all anthropometric indices. However, ABSI did not exhibit any association between the MetS and IR. The ABSI adjusted regression coefficients (beta values) were 0.403 for high-sensitivity C reactive protein, 0.077 for tumor necrosis factor-alpha, and 0.022 for interleukin-6. BRI and WC were also significantly associated with three inflammatory factors. Comparing the lowest with the highest quintile, BRI had the largest ORs for MetS (OR, 5.778; 95% confidence interval ICI], 2.954-11.303; P < 0.01) and IR (OR, 6.212; 95% CI, 2.912-13.250; P < 0.01). Conclusion: Only BRI and WC, not ABS1, can significantly determine the presence of MetS and IR BRI showed the optimal capability to identify IR in obese and overweight population. (C) 2018 Elsevier Inc. All rights reserved.