In order to confirm the anti-rejection effect of Tripchlorolide (T4), we compared the mean survival time of cardiac allograft, scores of pathological damage of the heart, the generation of IL-2 from splenocytes stimulated by ConA, and the serum level of sIL-2R in the heart transplant model (Lou-->F344) that received either cyclosporine or T4. The present study has shown that T4 could prolong the MST of cardiac allograft and significantly decrease the degrees of pathological damage of the transplant heart. The results indicated that T4 might be used as new anti-rejection drug in organ transplantation.