Many friends with type 1 or type 2 diabetes have unsatisfactory blood sugar control and various complications come out over time, the most serious of which are kidney and eye, i.e. kidney failure and blindness. In some patients, even though the blood sugar tested 3 or 4 times a day is normal, complications still appear, and then continuing to apply insulin therapy cannot solve the problem. In this case, pancreas transplantation can be considered, especially for patients whose blood glucose is not satisfactorily controlled by insulin therapy or whose diabetes complications are still progressing, pancreas transplantation should be performed to solve the problem at root. Why is it necessary to perform pancreas transplantation instead of continuing insulin therapy for this type of patients? Simply put, human blood glucose and insulin levels fluctuate and are dynamically regulated all the time (every second), and exogenous pre-insulin therapy is far from the precision and frequency of such regulation.