Patients with painful mouth ulcers can go to the hospital, use topical medication and apply other treatments. 1. Go to the hospital: For patients with painful mouth ulcers, they should go to the hospital and use medication under the guidance of the doctor. The most common types of mouth ulcers are recurrent mouth ulcers and traumatic ulcers, which usually do not cause severe pain, and are only painful when eating, due to irritation. Some cancerous ulcers can be painful and should be seen by a doctor to rule out cancerous ulcers. 2. Local application of anesthetic: pain can be relieved by local application of lidocaine drugs, or choose to play a role in isolation of drugs, such as tretinoin oral ointment, which can protect the trauma, so that the pain of mouth ulcers to reduce, but also can be used to promote the healing of drugs, such as recombinant bovine alkaline growth factor and so on. Severe mouth ulcers should be treated early to avoid infection as well as pain, which can seriously affect the patient’s functioning and quality of life. Diet should be light, drink more water, porridge, etc. to regulate the stomach and intestines, but also eat more vegetables and fruits to supplement vitamins, the use of drugs need to follow the doctor’s instructions.