Mouth ulcers are self-limiting diseases that generally heal in about 12-14 days but are prone to recurrence. Mouth ulcers are the most common type of oral mucosal disease, and the majority of people experience mouth ulcers. The clinical manifestation of red, yellow and soreness is predominant, and pain is the main reason for consultation. There are many causes of mouth ulcers, which are now considered to be related to psychosocial, mental stress, local irritation, trauma, immunity, sleep deprivation, vitamin deficiency, genetics, etc. One should answer the doctor’s medical history inquiry truthfully and actively search for possible causes. The treatment method is based on local and systemic treatment. Firstly, remove the stimulating factors, such as residual roots and crowns, bad denture, joint trauma, etc. Local watermelon cream spray, growth factor spray, ulcer paste, etc. can be used to promote local healing; the systemic treatment can be oral oral inflammation clear granules and vitamin supplement. After the occurrence of mouth ulcers, first of all, you should relax your mind, do not have to be too nervous, anxiety, even without drug treatment generally 2 weeks can be healed. Usually keep oral hygiene, rinse your mouth in time, eat more vegetables and fruits, increase water intake, ensure sufficient sleep, and maintain a good rest routine and mentality. However, after removing local factors, if the ulcer does not improve significantly after 2 weeks or more, you need to be alert and should go to the hospital stomatology department in time.