Three new spirostane-type glycosides (1-3) were isolated from the whole plant of Allium flavum. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as (20S,25R)-2α-hydroxyspirost-5-en-3β-yl O-β-D-xylopyranosyl-(1→3)-[β-D-galactopyranosyl-(1→2)]-β-D-galactopyranosyl-(1→4)-β-D-galactopyranoside (1), (20S,25R)-2α-hydroxyspirost-5-en-3β-yl O-β-D-xylopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)]-β-D-galactopyranosyl-(1→4)-β-D-galactopyranoside (2), and (20S,25R)-spirost-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→2)]-β-D-glucopyranoside (3). The three saponins were evaluated for cytotoxicity against a human cancer cell line (colorectal SW480).