There are many reasons for stomach pain at night, such as genitourinary system diseases, pancreatic and spleen diseases, hepatobiliary system diseases, gastrointestinal diseases and so on. 1. Genitourinary diseases: for example, adnexitis, adnexal cysts, urinary tract infections, cystitis, urinary stones, and so on. Tummy pain caused by genitourinary system diseases is usually in the area of the lower abdomen. 2. Pancreatic and spleen diseases: for example, splenic infarction, pancreatitis, etc., manifested as pain on one side of the abdomen. 3. Hepatobiliary system diseases: for example, cholecystitis, acute and chronic hepatitis, gallstones, etc. The stomach pain caused by these diseases is characterized by pain in the right upper abdomen. 4. Gastrointestinal diseases: for example, intestinal obstruction, acute and chronic gastritis, peptic ulcer and so on. Tummy pain caused by gastrointestinal diseases is characterized by a certain relationship with dietary factors. There are many other reasons for stomach pain at night, such as a cold abdomen, etc. It is recommended that patients should consult the doctor in time, improve the examination, clarify the cause of the disease, and treat it in time, so as not to delay the condition.