Two triterpenoid saponins have been isolated from the seed kernels of Entada rheedii. Their structures have been established using 1D- and 2D-NMR and mass spectrometry as 3-O-beta-D-xylopyranosyl-(1-->3)-O-alpha-l-arabinopyranosyl-(1-->6)-2-acetylamino-2-deoxy-beta-D-glucopyranosylentagenic acid 28-O-beta-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (Rheediinoside A, 1) and 3-O-beta-D-glucopyranosyl-(1-->3)-O-[beta-D-xylopyranosyl-(1-->3)-alpha-l-arabinopyranosyl-(1-->6)]-2-acetylamino-2-deoxy-beta-D-glucopyranosylentagenic acid 28-O-beta-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (Rheediinoside B, 2). Compounds 1 and 2 were tested for their antiproliferative activity against T98G, A431, PC3 and B16-F1 cell lines, and further for their antioxidant properties. Moderate cytotoxic potency and antioxidant properties were found for these compounds whereas Rheediinoside B was in all assays more active than Rheediinoside A.