Pain on the left side of the navel can be caused by a variety of reasons, summarizing the common three categories: 1, the left upper abdominal pain is most common in the spleen and pancreatic diseases, the spleen is mainly hypersplenism caused by splenomegaly, pancreas is mainly acute and chronic pancreatitis. 2, the left side of the middle abdominal pain is mainly in the gastrointestinal function of the patients, such as constipation or diarrhea patients. 3, the left lower abdominal pain is most commonly found in the gastrointestinal function of the patient is not good. In addition, urinary tract infections and certain gynecological diseases in women can also cause pain in the left lower abdomen. Of course, the above is just a rough estimate from the symptoms, parts, to confirm the diagnosis, but also need further clinical examination.