The normal clinical reference range for platelets is (100-300) × 10^9/L. Usually, when the platelet level in the serum is <100 × 10^9/L, it is called low platelets, and such a situation is not recommended for the New Crown vaccine. Especially when the platelets are <20×10^9/L, the body has a greater tendency to bleed, and bleeding may occur and the puncture site may not be easily stopped if the neo-crown vaccine is administered. Low platelets may be caused by abnormal platelet production, excessive consumption and destruction, and uneven platelet distribution, mostly due to diseases such as aplastic anemia, upper respiratory tract infection, megaloblastic anemia, liver cirrhosis, and disseminated intravascular coagulation. If the cause of neocrown vaccination is not identified, an allergic reaction may occur or aggravate the existing condition, therefore, neocrown vaccination is not recommended. Patients are advised to go to the hospital for routine blood tests, coagulation tests, and other tests to determine the cause of the disease and then treat the cause. It is safer to wait for the platelets to return to normal before receiving the vaccine. If the primary platelets are slightly low and the patient has no uncomfortable clinical symptoms, it is generally possible to receive the New Crown vaccine, but it is best to consult with the doctor at the vaccination center before receiving the vaccine to avoid adverse consequences.