Staying up late is not the main cause of gastric cancer, but the low immunity of the body when staying up late for too long may induce the possibility of gastric disease or other malignant diseases. The occurrence of gastric cancer is mainly caused by the patient’s dietary structure, gastric polyps and gastric ulcers. When the immunity of the patient is further depressed after staying up late for a long time, it may easily cause gastritis and gastric ulcers. When gastritis ulcer is not treated for a long time or recurring, it induces atrophic gastritis and develops into atypical hyperplasia, which eventually tends to cause the possibility of gastric cancer. In order to reduce or lower the risk of stomach cancer, we should start from living and eating habits, avoid long-term and repeated late nights, take proper rest, and avoid spicy and stimulating food in diet.