There are many causes of abdominal enlargement, both physiologic and pathologic. Physiological common is obesity, pathological causes mainly include peritonitis, ascites, abdominal tumors and so on. 1. Physiological: including general obesity, abdominal obesity and so on. It is mainly related to life and diet, such as less exercise, eating more greasy food. There are no uncomfortable symptoms, such as severe obesity may appear after the activity of shortness of breath, fatigue and other symptoms. 2. Pathological: common peritonitis, cirrhosis, tuberculous peritonitis, ascites caused by primary or metastatic tumors in the abdominal cavity, hypoproteinemia, intestinal tumors, gastric tumors and so on. Most of them have related medical history and are accompanied by uncomfortable symptoms, such as cirrhosis ascites, most of them have history of hepatitis, which may be accompanied by symptoms such as loss of appetite, fatigue, jaundice and so on. It is recommended to consult a doctor in time to determine the specific cause by a professional doctor.