Abstract: With the improvement of surgical technique of heart transplantation and clinical application of potent immunosuppressant, the quantity of heart transplantation and the survival time of heart allograft have been significantly improved. However, a series of complications, such as right ventricular failure, ischemia-reperfusion injury, acute rejection, "Quilty lesion", infection and chronic rejection characterized by transplant coronary artery disease (TCAD) may still occur at different stages after heart transplantation. The application of endomyocardial biopsy (EMB) makes it possible to observe and understand the pathological features of multiple complications of heart allograft including rejection, which has become the most accurate diagnostic tool for postoperative complications. In this article, the brief history of heart allograft pathology, main postoperative complications and pathological diagnostic criteria, and cutting edge research progress on diagnostic criteria of rejection were illustrated, aiming to bring clinical benefits to more recipients undergoing heart transplantation.