A new triterpenoid saponin, oleiferasaponin A(1), was isolated from tea seed pomace (Camellia oleifera Abel). The structure of oleiferasaponin A(1) was elucidated on the basis of chemical and physicochemical evidence and was found to be 22-O-cis-2-hexenoyl-A(1)-barrigenol 3-O-[beta-D-galactopyranosyl(1 -> 2)] [beta-D-glucopyranosyl(1 -> 2)-alpha-L-arabinopyranosyl(1 -> 3)]-beta-D-glucopyranosiduronic acid. PC12 cells injured with H2O2 were used as the model to test the protective effects of oleiferasaponin A(1). The results indicated that oleiferasaponin A(1) can potentially prevent the H2O2-induced cell death of PC12 cells.