Abstract: Objective 　To investigate the effect of inhibiting angiogenesisby celastrol. Methods 　The tumor inhibitory rate and the vascular density were tested in animal tumor model with experimental t reatment . The expression of VEGF and bFGF were measured by immunohistochemist ry. Results 　The tumor inhibitory rate was 46. 86 % in celast rol (3mg/ kg), and was 60. 2 % in combined group . The int ratumoral microvessel density(MVD), expression of VEGF and bFGF in combined group and celastrol (3mg/ kg) group were lower than the cont rol and 5-Fu group ( P < 0. 01) . Conclusion 　Celast rol have inhibitory effect on S₁₈₀ sarcoma and strong inhibitory effects on angiogenesis. Its mechanism may be associated with the down-regulating of VEGF and bFGF expression.