A steroidal sapogenin was isolated from the leaf of Yucca filamentosa L. (Liliaceae) and it was found to be tigogenin from the measurement of physical constants of this sapogenin and its derivatives. Treatment of tigogenin with acetic anhydride to cyclize its side chain and subsequent oxidation with chromium trioxide afforded Δ16(17)-3β-acetoxyallopregn-16-en-20-one, m.p. 163°.