There is no contraindication to the New Crown vaccine for mouth ulcers, which strictly speaking does not affect the New Crown vaccine. It varies from person to person and requires a detailed examination at the hospital to determine if the vaccine can be administered. Usually, patients with mouth ulcers have no abnormalities and can receive the New Crown vaccine; however, if patients with mouth ulcers have fever symptoms or some other abnormalities, the New Crown vaccine is not recommended. Most of the mouth ulcers are caused by poor oral cleaning or lack of vitamins, folic acid, iron, zinc and other trace elements. If it is a simple mouth ulcer with stable symptoms, you can get the New Crown vaccine normally and observe closely for any adverse reactions after the injection. If the patient is worried, he can get the vaccination after the mouth ulcer is healed. If the oral ulcer causes other symptoms, such as infection in other parts of the body due to the spread of inflammation, accompanied by symptoms such as fever or mucosal erosion, the infection needs to be controlled and the vaccination should be administered after the infection and ulcer are cured. In addition, if it is a chronic or long-standing mouth ulcer, it is necessary to pay attention to any other abnormal manifestations, such as unexplained bleeding, white spots or red spots in the mouth, accompanied by local lumps or swollen lymph nodes, then it is possible that tongue cancer has occurred, and it is necessary to go to the hospital for examination to confirm the diagnosis, and in this case, it is also necessary to postpone the vaccination of the new crown vaccine.