Corneal transplantation is an effective treatment for corneal blindness, and it is the only hope for patients with corneal blindness. Cornea has no blood vessels and no lymphatic vessels, which is called immune privilege organ, so the success rate of corneal transplantation is significantly higher than that of other organ transplantation, but the rejection reaction after corneal transplantation is still the main reason for the failure of corneal transplantation. The directional movement of immune cells to lymphoid tissue and inflammatory sites is the mainly immune response after organ transplantation. And the regulatory T cells(Treg)play a key role in immune regulation, which can induce immune tolerance by regulating and inhibiting the activation of effector T cells and reduce the rejection reaction after corneal transplantation. In addition, this review also discussed the effectiveness of applying cordyceps sinensis extract FTY720 to enhance the function of Treg. Based on this, we briefly reviewed the sources, mechanism of action and treatment of Treg after corneal transplantation, so as to provide some reference for the subsequent clinical application transformation and basic research.