Usually coughs in adults are occasionally accompanied by vomiting, but coughs in babies are often accompanied by vomiting. The formation and recurrent onset of cough is often the result of a combination of many complex factors. It may be caused by some inhalation, by an infection, by a dietary relationship, or by a change in climate, mental factors, exercise, medication, etc. Vomiting is caused by external evil offending the stomach, poor diet, emotional disorders, and physical weakness after illness. So we can see that some children vomit when they cough may be due to poor diet and emotional disorders. Children’s digestive system is not fully developed, but sometimes they eat food that is not taboo, or things that get stuck easily, which is not easy for adults to have problems, but children are very easy to get stuck in the oropharynx. In addition, the child’s spleen and stomach indigestion can also lead to vomiting. Plus the respiratory system is not fully developed at the same time, for cough reflex is poor, so when coughing, the function of bronchial smooth muscle contraction is limited, if there is phlegm at this time, children’s airways are narrower, cilia movement is poor, phlegm is not easy to discharge, phlegm can not be smoothly discharged, a large amount of phlegm accumulation in the trachea and bronchi, affecting respiratory function, so the baby vomits. But we need to understand a misconception, in fact, cough is also a protective physiological phenomenon of the child, so in severe cases as long as the appropriate medication according to the symptoms can be used.