Whether it is normal to have a high fever after the third shot of the new coronavirus vaccine cannot be generalized, but needs to be decided according to the body temperature, time and other symptoms and other reasons. 1. Body temperature: Generally, after receiving the booster shot of the new coronavirus vaccine, adverse reactions may occur, such as fever, fatigue, headache and other symptoms, if the vaccinee has a fever of less than 38.5 ℃ and no other uncomfortable symptoms, it is a normal phenomenon. If the body temperature is greater than 38.5 ℃ and accompanied by other symptoms of discomfort, is an abnormal phenomenon. 2. Time: After receiving the booster shot of the new coronavirus vaccine, a high fever, under normal circumstances, can return to normal in about three days, is a normal phenomenon. If the disease does not improve or worsens after three days, it is abnormal. 3. Other symptoms: If there is high fever, fatigue and no other discomfort after vaccination, it is normal, but sore throat, runny nose and other phenomena are not normal. When an adverse reaction occurs after the third injection of the new coronavirus vaccine, if you are not sure, you should go to the hospital for examination and diagnosis, and carry out targeted treatment as soon as possible, so as to avoid the impact on the body.