Many studies suggest that the average life expectancy of patients with type 2 diabetes is lower than normal, but the actual prognosis is closely related to the presence or absence of complications, disease control and treatment of patients and cannot be generalized. Theoretically, patients with type 2 diabetes who are free of complications, have an individualized treatment plan, and have good compliance have a survival that is no different from that of normal individuals. In practice, however, the survival of patients with type 2 diabetes varies widely in terms of adherence to treatment. If a combination of diet, exercise, weight loss and medication is administered to keep blood glucose within the normal range, chronic complications can be avoided and people with type 2 diabetes can live as healthy a life as a normal person. However, if blood glucose is poorly controlled for a long time and is accompanied by other physical diseases, their life expectancy will be shortened accordingly. If treatment is not timely when complicating diabetic ketoacidosis, it can cause shock, multi-organ failure and other symptoms, and death may occur in a few hours at the earliest. In conclusion, patients with type 2 diabetes should strengthen health education, nutritional therapy, physical exercise, condition monitoring, prevent complications, and adhere to regular consumption of hypoglycemic drugs, and if necessary, inject insulin-like drugs for treatment.