Although diabetic patients have been in contact with insulin for a long time, not many of them can regulate its use, and the popularity of this knowledge still needs to be improved. 1, the choice of injection site (1) abdomen: is the preferred site for insulin injection, the absorption rate of insulin in the abdomen reaches 100%, the absorption rate is faster and the subcutaneous tissue is thicker, which can reduce the risk of injection to the muscle layer, pay attention not to inject insulin within 5cm from the umbilicus. (2) Outer upper arm: The subcutaneous layer of the arm is thin and must be pinched up to inject the skin when injecting, so it is not convenient for self-injection and can be injected with the assistance of others. The insulin absorption rate of the subcutaneous tissue of the arm is 85%, and the absorption rate is faster. (3) Anterior and lateral thighs: they are more suitable for self-injection, the subcutaneous layer is thin, the skin must be pinched up for injection, and the insulin absorption rate of subcutaneous tissues is 70%, and the absorption rate is slow. However, it should be noted that there are more blood vessels and nerves distributed in the inner thighs, which are not suitable for injection. (4) Buttocks: the subcutaneous layer is the thickest, and the skin may not be pinched up when injecting. Because of the low absorption rate and slow absorption rate of insulin in the buttocks, it is less used and can be injected with medium and long-acting insulin. 2. Rotation of insulin injection sites (1) 4 quadrants of abdominal rotation pattern (2) equal division of thigh and buttock rotation pattern Rotation of injection sites can avoid the trauma caused by repeated injection at the same site, so it is necessary to change injection sites frequently. The abdominal injection site can be divided into four quadrants, and the thigh or buttock injection site can be divided into two quadrants equally, and injections can be given in one of the quadrants each week, rotating in a clockwise direction. When injecting at any site, the distance from the last injection site should be at least 1 cm.