Insulin injection should be performed on the side and below the navel, not above the level of the navel or around the navel. Since the area around the navel is rich in capillaries, it is easy to cause bleeding danger. The abdomen is the preferred site for insulin injection, which can make the insulin absorb quickly and take effect faster, followed by the upper arm, outer thigh and buttocks. When injecting, attention should be paid to the disinfection of the skin. 75% medical alcohol should be used for disinfection, and after disinfection, wait for the alcohol to air-dry before injecting to avoid stimulating the skin of the injection site. The injection of one site often will lead to the atrophy of subcutaneous fat and the formation of hard knots, which will affect the absorption of insulin and affect the efficacy of the treatment, so be sure to change the injection site often and replace the needle for injection once.