Stomach cancer pain occurs at variable times, and pain from duodenal ulcers usually occurs at night. Stomach cancer patients will have abdominal pain. In early stage, the pain is not obvious and may be hidden pain in the upper abdomen. With the development of the disease, patients may have persistent or intermittent epigastric pain at irregular intervals, occasionally rhythmic pain, which is aggravated after meals. When cancer metastasis occurs, patients will have pain in the corresponding metastatic site. Patients with duodenal ulcer often have epigastric pain at night, which can be diagnosed by gastroscopy, and they can take omeprazole and other medications as prescribed by the doctor.