Objective The prevalence of obesity is constantly increasing. Multiple metabolic complications are related to obesity, including type 2 diabetes mellitus and non-alcholic fatty liver disease(NAFLD). Our study aimed to investigate the prevalence of obesity comorbidities and its association with BMI. Methods 765 individuals who visited the multidisciplinary clinic for obesity in Peking University First Hospital from 2015, Jun. to 2018, Sept. were enrolled in this study. The height, body weight, waist circumference, hip circumference were measured during the first visit. Body adipose percentage and basal metabolic rate were recorded. Questionnaires for daily food intake, comorbidity, and lifestyle were recorded. Fasting insulin, C peptide, glucose, HbA1C , uric acid, liver enzymes and lipid profile were measured. Statistical analysis was performed using SPSS 16. 0, and P<0. 05 was considered as statistical significant. Results Daily energy intake was higher in obesity group [ obese vs non-obese, (2136.6±739.4vs1905.7±468.4)kcal/d,P=0.046].Hypertension,NAFLDandgoutriskincreasedsignificantly in obesity group (obese vs non-obese, 36.0％vs 24.5％, P=0.02;76.5％ vs 60.6％, P<0.01;6.9％ vs 1.8％, P=0.04, respectively) . Family history of obesity and diabetes increased in obesity group ( obese vs non-obese, 64.5％vs 53.6％, P=0.03;47.4％vs 37.3％, P=0.048). Fasting insulin and C-peptide levels were higher in obesity group [obese vs non-obese, (24.8 ± 15.3 vs 13.6 ± 9.5)μIU/ml, P<0.01;(3.72 ± 1.40 vs 2.70 ± 1.16)μIU/ml, P<0.01). Liver enzymes increased significantly in obesity group [obese vs non-obese, (47.2±45.4 vs 23.3±21.4)U/L, P<0.01; ( 30. 4 ± 24. 0 vs 19. 9 ± 8. 5 ) U/L, P=0. 001 ] . Conclusions Obesity population had higher risk of hypertension, NAFLD and gout. Fasting insulin, C-peptide, liver enzymes, and UA also increased significantly in these patients. It is critically important to those obese individuals for regular screening of NAFLD and diabetes mellitus.