In order to investigate the pathologic features of cardiac and pulmonary allografts, endomyocardial biopsies (EMB) and transbronchial lung biopsies (TBLB) were studied in 3 patients after lung and heart transplantation. 2 autopsy examinations after a cardiac and a combined heart and lung transplantation were included in this study. The results demonstrated that the presence and the severity of allograft rejection were closely related to the degree of interstitial and perivascular lymphocyte infiltration. Parenchymal injuries may sometimes be a concomitant sign. One patients died suddenly 7 months after cardiac transplantation because of acute severe allograft rejection in combination with allograft coronary disease. Another patient who received combined heart and lung transplant died early after the operation due to coronary thromboembolism. The patient who received a single lung transplant has already survived 16 months. TBLB at 11 and 13 months after the operation showed the recurrence of pulmonary sarcoidosis in the donor lung. Our study confirmed that EMB and TBLB provided useful information for acute allograft rejection after heart and lung transplantation.