Compared with conventional insulin, ultra-short-acting insulin is absorbed three times faster than human insulin by subcutaneous injection, has rapid onset of action and short duration, and can control postprandial blood glucose more effectively, and ultra-short-acting insulin is more flexible in use. Ultra-short-acting insulin is mainly used to control postprandial blood glucose, but it can also be used in combination with medium-acting insulin to control evening or morning hyperglycemia. Because of the rapid onset and short duration of ultra-short-acting insulin, it should be injected immediately before meals and carbohydrate-containing food should be eaten within 10 minutes of administration to prevent hypoglycemia caused by excessive time. Local reactions such as skin redness, subcutaneous nodules and subcutaneous fat atrophy may occur at the site of ultra-short-acting insulin injection, and the injection site should be changed frequently.