Assay-guided fractionation led to the isolation of nine beta-dihydroagarofuran sesquiterpenoids from the fruits of Celastrus orbiculatus. All isolated beta-dihydroagarofuran sesquiterpenoids were tested for their cytotoxic activity against human melanoma A375-S2 and human cervical carcinoma Hela cell lines. Among them, compounds 1-5 and 7 showed cytotoxic activity. Compound 3 exhibited promising cytotoxicity against both human melanoma A375-S2 and human cervical carcinoma Hela cell lines. The structure-activity relationship was discussed briefly.