Stomach pain of advanced gastric cancer should be treated with oral painkillers or intramuscular injection of painkillers. The reason of stomach pain in advanced stage stomach cancer is mainly due to tumor enlargement, or tumor recurrence and metastasis in the abdominal cavity, including planting and spreading, and so on. At the same time, the tumor may invade the retroperitoneal nerve, resulting in very obvious abdominal pain and back pain. Generally, oral painkillers are needed to deal with the symptomatic pain, such as oral anti-inflammatory drugs of antipyretic and analgesic type, including ibuprofen or celecoxib, etc. If the pain is still very obvious, oral painkillers can be used. If the pain is still very obvious, you can take oral opioid analgesics, such as Mescaline, Oxycontin, or intramuscular injection of analgesics, such as Dulcolax or morphine and so on. If the patient’s condition is very serious can not eat, also can not take oral analgesics, can consider using fentanyl transdermal patch in the navel outside the external application.