Two new monodesmosidic saponins were isolated from an aqueous extract of the Ethiopian strain 44 of Phytolacca dodecandra. Their structures were established as 3-0-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-galactopyranosyl-(1-->3)] -beta-D-glucopyranosyloleanolic acid and 3-O-beta-D-xylopyranosyl-(1-->6)-O-beta-D-gluco-pyranosyl-(1-->3)]-beta -D-glucopyranosyloleanolic acid mainly by spectroscopic methods (LSIMS, H-1 NMR, COSY, NOESY, TOCSY, J-resolved H-1 NMR, C-13 NMR, HETCOR). The saponins are potent molluscicides against the schistosomiasis transmitting snail Biomphalaria glabrata with LC50 values of 2 and 5 ppm, respectively.