Abstract: A series of novel derivatives of betulinic acid(BA)-nitrate and BA-furoxan hybrids were synthesized by coupling NO donors with BA via various linkers.The compounds were structurally characterized by IR,MS and ¹H NMR,and their anti-tumor activity was determined in human hepatocellular carcinoma HepG2 cells and murine melanoma B16 cells by MTT assay.The preliminary results indicated that BA-furoxan conjugates exhibited stronger cytotoxic activity than BA in HepG2 and B16 cells and were worthy of further investigation.