Cyclosporine A is a new and potent immunosuppressant with high specificity and is widely used in controlling a variety of immunological rejection after organ transplantation. Research found that cyclosporine A suppresses the immune rejection in moderate to severe dry eye syndrome treatment. For mooren ulcers and autoimmune eye diseases, it has a significant effect. The application progress of Cyclosporine A in clinical ophthalmology is now reviewed.