A new saponin, named smilageninoside, mp 265-7 degrees C, was isolated from rhizomes of Anemarrhena asphdeloides by conventional method. The structure of smilageninoside was identified on the basis of IR, 1HNMR, 13CNMR and FAB-MS. Its structure was smilagenin 3-O-[beta-D-glucopyranosyl