From the bulbs of Allium giganteum, three new steroidal saponins, (25R)-3-O-acetyl-5α-spirostan-2α, 3β, 5α, 6β-tetraol 2-O-β-D-glucopyranoside (2), (25R)-5α-spirostan-2α, 3β, 5α, 6β-tetraol 2-O-β-D-glucopyranoside (3) and (25R)-3-O-benzoyl-5α-spirostan-2α, 3β, 5α, 6β-tetraol 2-O-β-D-glucopyranoside (4), have been isolated. The new saponins are unique in structure having the sugar moiety at the C-2 hydroxyl position on the steroidal skeleton.