Vomiting is very common in tumor patients no matter they are in early or late stage, especially in late stage patients, and the common causes are as follows: 1. tumor: such as primary gastrointestinal tumor or pelvic and abdominal tumor, the chance of vomiting and other gastrointestinal symptoms is higher; such as other parts of the tumor metastasized to the pelvic and abdominal cavity compressing the gastrointestinal tract can also cause nausea and vomiting; 2. treatment: such as radiotherapy and chemotherapy, can be accompanied by nausea and vomiting 3, psychological and physiological factors; 4, electrolyte disorders: very common in clinical practice, which can also show nausea and vomiting. Different treatments for different causes can achieve twice the effect with half the effort.