There is generally no exact data on how many years a diabetic patient can live on insulin. If insulin is reasonably applied under the guidance of a doctor, it usually does not affect life expectancy. Insulin injection is an important method for diabetic patients to control their blood glucose. When the blood glucose can be controlled in an ideal state after taking insulin, and there is no complication or the complication is well controlled, it usually will not affect the life expectancy of the patients. If the glycemic control after insulin is poor and the complications are more serious, even end-stage renal failure may develop, which may seriously affect the survival time of patients. It is recommended to apply insulin to control blood glucose under the guidance of a doctor, and not to use medication on your own.