Abstract: A steroidal saponin has been isolated from the roots of Taccachanteraeri Andre', a folk medicine in Yunnan, which identified as diosgenin 3β-O-α-L-rhamnopyranosyl-(1→2)- O-α-L-rhamnopyranosyl-( 1 → 3 )-O-β-D-glucopyranoside ( 1 ) with stigmasterol (2) and daucosterin (3). Our studies support I. H. Burkill and A. Takhtajan's idea according to which Taccaceae would be the closest to Dioscoreaceae and be included in Liliales.