If a patient is still bleeding after 20 minutes of pressure after phlebotomy, first of all, it is necessary to clarify whether there is any abnormality of coagulation function, and then consider that it is caused by the improper way of patient’s pressure after exclusion. Normal people can stop bleeding by pressing the eye of the needle for about 5 minutes after a phlebotomy, but if the patient still bleeds after 20 minutes of pressure, the first thing to do is to find out whether there is any abnormality in coagulation function. This disease is mainly due to the high permeability of the patient’s blood vessel wall, the lack of coagulation factors in the body, the number of platelets is low and other factors, often resulting in patients with unexplained bleeding gums, nosebleeds and other symptoms, and will be bleeding for a long time after the blood test. If the patient excludes coagulation abnormalities, the patient is considered to be caused by factors such as improper pressure. After a normal blood test, the patient will be left with two needle eyes on the skin surface and on the wall of the venous blood vessel. If the patient presses the needle eye on the skin surface with only one finger, and the force is too light, it will lead to continuous bleeding from the needle eye on the wall of the venous blood vessel. At the same time, if the patient presses on the eye of the needle for a while and then releases it, and continues to press on it after noticing the bleeding, it can also happen that the vein still bleeds after 20 minutes of pressing on it after phlebotomy. If a patient occasionally bleeds after 20 minutes of phlebotomy, this is mostly due to improper pressure and should not be a cause for concern. However, if this phenomenon occurs frequently, patients should be examined to determine whether their coagulation function is normal.