It is very common for children to have a normal morning fever and a fever in the afternoon. In the case of Mycobacterium tuberculosis infection, it is easy to develop afternoon fever, and in addition to fever, there will be coughing, coughing up sputum, hemoptysis, lethargy, and night sweats. In the afternoon, the body temperature is already higher than in the morning, so the symptoms of fever are more likely to appear in the afternoon, or it may not be caused by Mycobacterium tuberculosis infection, but by a common viral or bacterial infection, so it is necessary to go to the hospital for specific tests. Routine blood tests, C-reactive protein, chest plain films and tests for antibodies to mycoplasma are necessary. If a common infection has occurred, it is necessary to choose appropriate antibiotics or antiviral drugs according to the type of infection to carry out anti-inflammatory treatment. For fever, if the temperature is high and exceeds 38.5 degrees, oral ibuprofen suspension is required. In the case of Mycobacterium tuberculosis infection, the child should be taken to a specialized tuberculosis hospital for targeted treatment.