Gastric cancer is one of the most common malignant tumors in the digestive tract, and its incidence rate is the first among all kinds of tumors in China, among which more than 95% are adenocarcinoma. Most of the early stages of gastric cancer have no obvious symptoms, or only minor digestive symptoms are not easily detected. Therefore, we should be alert to the early warning signs of gastric cancer so as not to delay the diagnosis and treatment. 1. Pain in upper abdomen. Upper abdominal pain is the most common symptom of gastric cancer. It starts as intermittent vague pain and is often diagnosed as gastritis or ulcer disease. 2.Upper abdominal discomfort. It is mostly a feeling of fullness or burning. It can be temporarily relieved and recurring. 3, loss of appetite, belching and other indigestion symptoms. The symptoms are a feeling of fullness after eating and active restriction of diet, often accompanied by recurrent belching. 4. Black stool or positive fecal occult blood. If black stool occurs without eating blood tofu, taking bismuth and other drugs, you should come to the hospital for examination as soon as possible. 5.Lack of energy, wasting and anemia. This is another common but non-specific group of stomach cancer symptoms. Patients often show fatigue and weakness due to loss of appetite and blood loss in digestive tract. At present, chronic gastric diseases such as chronic gastritis, gastric ulcer and gastric polyp have been recognized as precancerous lesions of gastric cancer, and these people are more prone to gastric cancer. Therefore, when symptoms of stomach pain, stomach area discomfort or digestive tract discomfort occur, they should go to hospital for gastroscopy or laboratory examination in time to raise their alertness.