Erythroplakia usually refers to erythroplakia, which is a skin disease. The etiology of erythroplakia is unclear, and may be triggered by factors such as circumcision, infection, or chronic inflammation. It will manifest as scaly erythema on the mucous membranes, and generally has a slow course, and may remain unchanged for many years. If not treated properly, it may also develop into invasive squamous carcinoma, which can metastasize to local lymph nodes or distant sites as the disease progresses. Erythema multiforme can occur naturally, usually on the glans, prepuce, and urethral opening, but may also occur on mucosal areas such as the oral mucosa, pubic area, and anus. It is solitary in more patients and can be multiple in a few. The damage is mainly rash-like changes. When the above symptoms appear in the body, it is also necessary to go to the dermatology department of the hospital in a timely manner, and confirm the diagnosis through the doctor’s physical examination, laboratory examination and pathologic examination and other related tests. Combined with the severity of the disease, to take corresponding treatment measures.