Patients have been oral ulcers, may be related to oral mucosal injury, genetic, celiac disease, leukoaraiosis and other factors. 1. Oral mucosal injury: when patients accidentally eat fish bones, gravel and other hard objects or water temperature is too high, food is too hot, etc., may damage the oral mucosa, in addition, the patient in the use of aspirin and other analgesic oral tablets for treatment of toothache, as well as the use of silver nitrate, tincture of iodine and other stimulating drugs, may also lead to local oral mucosal injury, which can cause oral ulcers. 2. Heredity: for patients with recurrent oral ulcers, there may be relevant genetic inheritance, therefore, the development of recurrent oral ulcers has a genetic predisposition. 3. Celiac disease: Celiac disease, also known as wheat gluten enteropathy, is a chronic autoimmune intestinal inflammatory disease. Celiac disease patients may experience unexplained diarrhea, abdominal cramps, bloating, mouth ulcers and other symptoms. 4. leukemia: leukemia is a chronic systemic vascular inflammatory disease, mainly manifested as recurrent oral ulcers, genital ulcers, pharyngitis and skin damage, etc. Patients have been oral ulcers, which may be caused by leukemia. In addition, long-term emotional fluctuations, poor sleep, lack of micronutrients, AIDS, etc. may also cause mouth ulcers all the time, it is recommended that the patient timely medical examination, to clarify the cause of the targeted treatment.