Mooren’s ulcer is a chronic, painful ulceration of the cornea with a steep, overhanging central and leading edge that starts in the periphery and may progress centrally or circumferentially to involve the entire cornea. Mooren’s ulcer can only be diagnosed in the absence of an infectious or systemic cause, and must be differentiated from other corneal abnormalities, such as Terrien’s marginal degeneration. The etiology of Mooren’s ulcer is still unknown, and evidences show that it is an autoimmune corneal disease. Although recent research proposed a possible association with the hepatitis C virus, it has not been confirmed by large clinical trials. Mooren’s ulcer is hard to manage and can cause blindness. The response to medical intervention is typically poor, and the visual outcome can be devastating. It was reported that the incidence of Mooren’s ulcer in China was 0.03 percent. LKP surgery of Mooren’s ulcer removes antigenic targets of the cornea, prevents immunological reactions, reconstructs the anatomical structure of the cornea, prevents it from perforating, and improves vision. Our results indicate that the final healing rate of Mooren’s ulcer treated with resection of the corneal lesion and adjacent conjunctiva combined with LKP surgery is 89.6 percent, and the final healing rate of LKP plus topical 1 percent cyclosporin A is 95.6 percent. The anatomical structure of the cornea in 99.7 percent of the ulcerated eyes is preserved. We consider LKP surgery to be the most effective treatment of Mooren’s ulcer at present. Optimal treatment of Mooren’s ulcer to result in a favorable outcome to the patient depends upon: Thorough removal of corneal ulcer and infiltrate, Excision of conjunctiva and episclera adjacent to the corneal ulcer combined with an LKP, A good host-graft junction and Topical use of steroids and 1 percent cyclosporin A postoperatively. The LKP surgery plus 1 percent topical cyclosporin A is an effective treatment of Mooren’s ulcer when the above four principles are practiced. Even if one procedure fails, re-grafting can give the patients a chance for proper healing of the ulcer and maintaining visual acuity.