Postoperative systemic metastatic pain of gastric cancer can be treated by medication (such as morphine), chemotherapy and radiotherapy. 1. Drug treatment: when the pain is more serious and cannot be tolerated, it can be treated with drugs such as morphine and oxycodone hydrochloride under the guidance of physicians. 2. Chemotherapy: this way is to use chemical drugs to improve the patient’s quality of life and prolong the patient’s survival, commonly used drugs are cisplatin, fluorouracil and so on. 3. Radiotherapy: this treatment method mainly kills cancer cells through radioactive high energy beams. After gastric cancer patients have the symptoms of systemic metastasis and pain, they should go to the hospital in time, under the guidance of physicians to carry out relevant treatments, and strictly follow the doctor’s instructions to use medicines.