Background: A body mass index ≥95 percentile increases 40 times the risk of diabetes. The hyperinsulinemia secondary to the resistance of insulin and obesity is associated to the development of acanthosis nigricans. The objective of current study was to associate acanthosis nigricans with childhood obesity with alterations in the curve of glucose tolerance.Methods: In current study 90 children were evaluated with obesity and acanthosis nigricans of which only 34 concluded the study. Glucose, cholesterol and triglycerides levels were determined while in fasting state, and glucose tolerance curve was conducted. The statistical analysis was done by determining X², Fisher´s test and U, Mann Whitney test.Results: Statistically significant difference was found between glucose levels at 2 hours and the presence of obesity and acanthosis nigricans (p<0.01).Conclusions: It is important that all the children with obesity and Acanthosis nigricans apply for a curve of glucose tolerance.