Dihydroartemisinin(DQHS)is obtained by reduction of artemisinin with NaBH4 as reductant,and then DHA-DQHS is prepared by esterification of docosahexaenoic acid with dihydroartemisinin in the presence of dicyclohexylcarbodiimide(DCC)and 4-dimethylaminopyridine(DMAP).Antitumor activity of DHA-DQHS against CA46,Molt4 and P388 cells is tested by MTT method in parallel with artemisinin and dihydroartemisinin.Results show that the 1H NMR and ESI-MS of DHA-DQHS are in agreement with its chmical structure.IC50 of DHA-DQHS on CA46,Molt4 and P388 cells are 0.024,0.076 and 0.105 mg·L-1 respectively,which are significantly lower than those of artemisinin and dihydroartemisinin,the reason for that is possibly owing to the tumor-targeting property of DHA.