With the arrival of autumn, many people are prone to mouth ulcers, which, although not a major disease, bring many inconveniences to life. The cause of its occurrence is still unclear, but it is generally believed to be related to immune abnormalities. Fatigue, climate change, excessive alcohol consumption, oral mucosa damage and other factors can often trigger, at first manifested as oral mucosa erosion, and later formed ulcers, can be a single occurrence, but also can be multiple occurrences. There are many treatment methods, but not many special effects. The author is a medical worker, several times a year to suffer from oral ulcers, has used a number of treatment methods, after being introduced to the use of watermelon cream spray, found good results, and introduced to other people, after some clinical observation, proved that can significantly improve the efficacy. Now the method is introduced as follows: use Guilin watermelon cream spray, generally available in pharmacies, when the oral mucosa erosion just appeared or after the mucosal injury, 3-4 times a day in the lesion spray on the appropriate amount (1-2 spray), and contains about 10 minutes, the lesion more in 1-2 days to improve and heal, most no longer transformed into ulcers. For those who have ulcers, can reduce the pain symptoms, but the role of accelerating healing is not as obvious as in the early use. This method is simple and practical, without side effects, and the key is to use it early in the lesion.