It is not recommended to evaluate the severity of the disease based on clinical symptoms. Vomiting yellow water and bitter water in the middle of the night is considered to be related to gastrointestinal diseases and central nervous system diseases, etc. It is recommended to consult a doctor in time for the above symptoms, so that a professional physician can make a clear diagnosis and evaluate the severity of the disease. 1. Gastrointestinal diseases: vomiting yellow water and bitter water in the middle of the night is usually bile, when patients with gastrointestinal diseases, such as acute gastroenteritis, vomiting is more serious, there is no food in the stomach can be vomited, bile will reflux from the duodenum upward, the symptom of vomiting yellow water and bitter water. 2. central nervous system diseases: when the patient occurs such as increased intracranial pressure, cerebral hemorrhage and other diseases, there will be a severe headache, vomiting and other symptoms, when the patient has no stomach contents, will also lead to vomiting yellow bitter water, but vomiting is often jet-like. When the patient appears in the middle of the night vomiting yellow water bitter water symptoms, it is recommended to go to the hospital as soon as possible, under the guidance of a professional physician to evaluate the severity of the disease.