Mucosal leukoplakia, or mucosal leukoplakia, is a common precancerous lesion, referring to the white keratotic disease that occurs in the mucous membranes of the oral cavity or vulva and other places. The etiology of mucosal leukoplakia has not been clearly defined, and it may be related to endocrine disorders, vitamin deficiency and other factors, and it is commonly found in the oral cavity of middle-aged and elderly men or the vulva of postmenopausal women. Clinically, the lesion damage site is manifested as dotted, flaky or striated gray or milky white keratinized spots, which have certain tendency of malignant transformation, generally transformed into squamous cell carcinoma. However, its malignant rate is low, generally only 4~6%. It is recommended that patients with mucous membrane leukoplakia should take local or oral medication under doctor’s guidance and follow up for observation, and once malignant transformation occurs, surgical excision should be carried out for treatment.