Objective: To investigate anti-tumor effect and possible mechanism of N-butanol extract of Daphne odora Var.Marginata in vivo. Method: Solvent extraction method was used for obtaining extraction from D. odora. Mouse model of transplanting tumor was used to study the in vivo anti-tumor effect of N-butanol extract of D. odora at different concentrations. MTT method was used to examine the effect of NK cell. ELISA method was used to examine IL-2 secreted by spleen cell. Result : N-butanol extract of D. odora could decrease the tumor weight in S180-bearing mice. It could raise IL-2 secreted by spleen cell

and obviously enhance the effect of NK cell. Conclusion: N-butanol extract of D. odora has anti-tumor activity in vivo and promote spleen cell secrete IL-2 and enhance the effect of NK cell.