Aims: To compare the magnitude of associations of the obesity indicators with the risk of prediabetes and diabetes. Methods: We performed an individually region-, sex-, and age-matched case and control analysis involving 42 918 Chinese adults aged 20-88 years (6876 matched prediabetes and normal glucose regulation [NGR] groups and 2873 matched newly diagnosed diabetes mellitus [NDM] and NGR groups). Results: Compared with their respective NGR controls, the participants with prediabetes or NDM had significantly higher mean levels of obesity indices as follows: waist circumference (cm), 85.3 vs. 81.8 and 87.9 vs. 82.9; waist-to-height ratio (WHtR), 0.531 vs. 0.509 and 0.546 vs. 0.514; and body mass index (BMI) (kg/m(2)), 25.4 vs. 24.1 and 25.9 vs. 24.2 (all P < 0.001). The odds ratios (95% confidence intervals) of NDM with waist circumference, WHtR, and BMI per standard deviation (SD) increase were 1.88 (1.80-1.97), 1.88 (1.80-1.97), and 1.69 (1.62-1.76) in the total population. Conclusions: Mean differences in the three obesity indices were around 0.3 SD between matched prediabetes cases and NGR controls, and around 0.5 SD between matched NDM cases and NGR controls. Waist circumference and WHtR were more strongly associated with diabetes than BMI among Chinese adults. (C) 2018 Elsevier B.V. All rights reserved.