Turning over the eyelid and finding an ulcer is usually due to conjunctivitis, which is related to infectious factors or autoimmune factors, etc. The inner surface of the eyelid is covered with conjunctival tissue, once there is inflammation formation, it may lead to localized conjunctival tissue erosion, thus forming ulcers, such as bacterial infection, viral infection, and so on. In addition autoimmune inflammation, is also one of the causes of ulcers in the conjunctival tissue. Patients should go to the ophthalmology department of the hospital, and the doctor will use the slit lamp microscope and other examinations to diagnose the specific causes. Conjunctivitis caused by bacterial infections can be treated with drugs such as levofloxacin eye drops, and conjunctivitis caused by viral infections can be treated with drugs such as ganciclovir eye drops. Conjunctivitis patients are advised to consult a doctor to assess their condition and follow the doctor’s instructions.