The causes of diarrhea in advanced stage of liver cancer are: liver cancer affects gastrointestinal function, impaired liver function and intestinal infection. 1. Influence on gastrointestinal function: when liver cancer develops into advanced stage, when the tumor is too big, it can cause pressure on gastrointestinal organs and other digestive organs; or when there is metastasis of gastric or intestinal tumors in advanced stage, it will affect the digestive and absorptive function of gastrointestinal tract, which will then lead to diarrhea. 2. Impaired liver function: liver is an important digestive organ, and the destruction of liver by cancer cells can cause its function to be reduced, which can lead to hypoalbuminemia, cause intestinal edema; or affect its digestive function, which can lead to diarrhea. 3. Intestinal infection: In addition, if patients eat unclean diet, coupled with poor immunity, diarrhea symptoms will easily appear. Diarrhea symptoms should consult a doctor in time, in order to clarify the diagnosis and standardize the treatment as soon as possible.