Abstract： Objective To investigate the impact of insulin resistance and insulin secretion on the development of glucose intolerance in Chinese. Methods Given 75 gram oral glucose tolerance challenge, 466 Chinese (189 normal weight, 277 overweight/obesity) were divided into normal glucose tolerance (NGT) group, impaired glucose tolerance/impaired fasting glucose (IGT/IFG) group, as well as type 2 diabetes (DM) group according to 1997 ADA criteria. Homeostasis model assessment (HOMA) was applied to assess the status of insulin resistance (HOMA IR) and basic function of pancreatic β cell (HOMA β cell). While insulinogenic index (the ratio of the increment of insulin to that of plasma glucose 30 min after a glucose load, △I 30 /△G 30 ) was performed to evaluate the early phase insulin secretion. Results Adjusted with age, sex, body mass index (BMI), body fat distribution indices (including abdominal visceral, subcutaneous, and femoral subcutaneous adipose tissue areas) and blood pressure, our data indicated that in comparison with NGT group, HOMA IR was increased significantly in IGT/IFG and DM group, especially overt in the overweight or obesity subjects. Meanwhile HOMA β cell and △I 30 /△G 30 were remarkably lower in IGT/IFG and DM group than in NGT group, particularly in DM group. Conclusion Insulin resistance and insulin secretion deficiency may play an important role on the worsening from normal glucose tolerance to glucose intolerance in Chinese individuals.