The significance of insulin and C-peptide release test has three points as follows: First, insulin and C-peptide release can understand the decay of human pancreatic B-cell function, for example, if the secretion of insulin and C-peptide is particularly low, it means the pancreatic islet function is particularly poor, and it can distinguish type 1 diabetes from type 2 diabetes. Second, insulin and C-peptide release test can understand the situation of insulin resistance in the body, if the insulin level in the body is particularly high and the C-peptide level is normal, it indicates the phenomenon of insulin resistance in the body. Third, the treatment plan can be determined by measuring insulin and C-peptide release test, for example, insulin treatment is needed if the insulin and C-peptide level is absolutely low. If the insulin and C-peptide levels are normal or low, the treatment can be carried out by oral medication to lower sugar.