Vomiting may be caused by vaccination in six-year-olds, but it is usually not serious and can be observed by paying attention to diet first. If the vomiting is frequent, it is necessary to consult a doctor actively to find out the cause of vomiting and carry out targeted treatment. After vaccination, some 6-year-old children may have vaccine reaction, such as vomiting, low fever, etc. Usually the vomiting is not serious and lasts for a short period of time, and can be gradually relieved by paying attention to diet (e.g., eating a small amount of light diet), and generally do not need special medication, but need to be closely observed. For children with frequent vomiting, it is necessary to actively consult the doctor, according to the presence of other symptoms (such as fever, diarrhea, abdominal pain, etc.), to determine the cause of vomiting (such as acute gastroenteritis, acute appendicitis, etc.). Specific treatment needs to be targeted according to the diagnosis. For acute gastroenteritis, oral montelukast can be taken to relieve symptoms. For acute appendicitis, oral antimicrobials (e.g., cefaclor) should be given to control the infection, and the need for surgery should be evaluated by a specialist. All of the above medications should be used under the supervision of a physician, and it is recommended that these children be seen by a specialist for evaluation.