Always grow mouth ulcers, is recurrent mouth ulcers, the cause of this disease is complex: 1, local irritation factors, such as residual crowns, residual roots, bad restorations in the mouth, etc. 2, nutritional factors, lack of vitamins, trace elements. 3, genetic factors, if both parents suffer from recurrent mouth ulcers, children are susceptible physique, also prone to disease. 4, psychological factors, mental tension, stress, also very 5, irregular work and rest, lack of physical exercise, lack of sleep, is also the cause of recurrent ulcers. Patients with recurrent mouth ulcers should first be seen in a hospital to remove local irritants in the mouth, eat more fruits, vegetables, and high-protein foods to enhance the body’s resistance to disease, supplement vitamins and trace elements, and maintain regular rest and rest, appropriate physical exercise, ensure adequate sleep, and maintain a happy mood, which can reduce the recurrence of mouth ulcers.