1.Reduce the stimulation and friction to the oral mucosa: avoid eating spicy, fragrant, warm and fire food, such as onion, ginger, leek, garlic, chili, pepper, beef, mutton and dog; avoid using tobacco, wine, coffee and stimulating drinks; avoid excessive consumption of acid, alkaline, spicy or baked and fried food. 2, pay attention to nutrition: eat more food containing zinc to promote wound healing, such as oysters, animal liver, lean meat, eggs, peanuts, walnuts, etc. Eat more fresh vegetables and fruits, such as tomatoes, eggplant, carrots, white radish, cabbage, spinach and other foods rich in vitamin B1, vitamin B2 and vitamin C, which are conducive to ulcer healing. 3, to pay attention to the absorption of vitamins: another important reason why patients with gastrointestinal diseases are prone to mouth sores is that it affects the absorption of vitamins in the body. Therefore, it is very important for paranoid people who often get mouth sores because they do not like to eat vegetables and fruits to eat more vegetables and fruits to keep their bowels open and prevent constipation. Drinking more water, eating more fiber-rich foods, and keeping the bowels open can also help reduce mouth sores. In addition, people who often have mouth sores can make some homemade herbal tea drinks, which can effectively prevent the occurrence of mouth sores when consumed properly in hot weather. 4. Maintain emotional stability and good habits: Stay in a relaxed, optimistic and cheerful mood to avoid getting angry due to irritability. People who are in a bad mood should be good at solving their own problems, be tolerant of others, live in harmony with others, and maintain an optimistic attitude toward life. At the same time, to develop a good routine, to ensure adequate sleep, avoid overwork. 5, to pay attention to oral hygiene: to pay attention to oral hygiene, develop good habits of brushing teeth in the morning and evening, rinse mouth immediately after meals, available salt water, saline, also available drug mouthwash, reduce oral bacteria, prevent secondary infection due to food residue aggravation. The above methods are only suitable for the prevention of this disease, if you are already a patient of mouth ulcer, please go to the regular hospital for examination and treatment in time.