Five lignans were isolated from the chloroform fraction of Acanthopanax chiisanensis Nakai root by open column chromatography. Their structures were elucidated as (-)-sesamin (1), helioxanthin (2), savinin (3), taiwanin C (4), and 3-(3",4"-dimethoxybenzyl)-2-(3',4'-methylenedioxybenzyl) butyrolactone (5) by spectral analysis. Among them, compounds 2, 3, 4, and 5 were isolated for the first time from this plant.