The clinical use of blood is strictly checked before application and therefore the requirements for blood donation are high. In general, blood tests are required before donating blood, usually for routine blood tests, liver function and indicators of certain infectious diseases, such as hepatitis B, hepatitis C, syphilis and AIDS, among others. Therefore, blood products that do not pass the test should not be used. There are several cases of failure, there may be infections with certain infectious diseases, the most common of which is hepatitis B. In addition, abnormalities in blood count may also occur in the case of unqualified blood donations, such as elevated red blood cells, increased or decreased platelets, etc. In addition, abnormal liver function or too high blood lipids can also result in a failed blood donation. Therefore, it is important to pursue the causes of failed blood donations to identify and treat the problem in a timely manner.