A bulge in the navel of an adult may be caused by an umbilical hernia, abdominal tumor, ascites, or umbilical infection. Umbilical hernia is a type of extra-abdominal hernia, often caused by congenital or acquired weakness of the abdominal wall and increased intra-abdominal pressure, so that the contents of the abdominal cavity protrudes from the weak part of the abdominal wall, which can be manifested as umbilical bulge. The umbilical hernia should be diagnosed by ultrasound examination, and hernia repair surgery should be performed in time. When primary or metastatic tumor occurs in the umbilicus, it can cause umbilical bulge, and abdominal ct examination and fine-needle biopsy puncture should be performed to clarify the diagnosis. When a large amount of ascites exists in the abdominal cavity, it will lead to an increase in intra-abdominal pressure and the symptoms of abdominal bulge and protruding umbilicus. It is mostly caused by liver cirrhosis, and should improve liver function and symptomatic treatment in time. In addition, navel skin infection caused by umbilicitis, skin tissue redness and swelling, and even abscess formation, the navel bulge can be seen on visual examination. Therefore, found that the adult navel bulging a bag, should be timely consultation, improve the examination, a clear diagnosis of the corresponding treatment as prescribed by the doctor.