Abstract: (5R)-5-hydroxyltripthiocyanatolide(compound 5) was synthesized with triptonide as starting material through hydroxylation, reduction and nucleophilic substitution. On the basis of NMR and HRMS analysis, the structures were characterized and the results showed that compound 5 was successfully synthesized. The biological activities of compound 5 were tested and the results showed that compound 5 had inhibition rate of 69.95% against human lung cancer cell(A549 cells) at the concentration of 10 mg/L, which was equivalent to the level of the positive control (5R)-5-hydroxyltriptolide(LLDT-8), indicating that compound 5 had a certain antitumor activity; compound 5 was found to exhibit less inhibitory effect on leukomonocyte activation than the parent compound; more safety than LLDT-8 was observed on cytotoxicity assay on 293T cells. Target compound might mean an antitumor molecule for further development.