Diabetic hyperosmolar state is an acute complication that often occurs in older patients with type 2 diabetes and is less common in patients with type 1 diabetes. The clinical presentation is similar to ketoacidosis, except that there are no ketone bodies in the urine and there is rarely acidosis. In diabetic patients, due to the increase of glucose in the blood, the osmotic pressure in the blood also increases, and the water in the blood is eliminated from the urine. If the blood sugar is not well controlled, it causes the patient to be dehydrated then it is easy to cause hypertonic coma. Once coma occurs, the patient’s mortality rate is also much higher than that of ketoacidosis coma, which once reached 40% to 70%, but now, although it has improved, it is still as high as 15% to 20%. Some diabetic patients are not aware of the disease and do not take regular treatment, or even misuse high sugar infusion due to other diseases, resulting in a significant increase in blood sugar. In addition, it is also easy to occur in acute situations such as stress, infection, angina pectoris or myocardial infarction, cerebrovascular accidents, surgical operations, etc. Hypertonic non-ketotic diabetic coma is also caused by hypertonicity in the elderly due to a reduced sense of thirst and insensitivity of the water intake center, resulting in too little water intake and blood concentration. The longer the hyperosmolar state lasts, the higher the mortality rate. Therefore, early prevention plays a decisive role in the mortality of hyperosmolar coma. Specific reference can be made to the following points: 1. Early detection of diabetes and reasonable control of blood glucose; 2. Prevention of various factors that can cause hyperosmolar state, such as infection, stress, hyperthermia, gastrointestinal water loss, burns, etc.; 3. Attention should be paid to hydration and regulation of osmolarity balance; 4. Avoid the use of glucose-raising drugs, such as glucocorticoids; 5. Middle-aged and elderly people should be especially alert to the occurrence of this disease, and it is best to go to the hospital regularly for blood glucose and It is best to go to the hospital regularly for blood glucose and osmolarity check.