Three new stilbenoids, including α‐(3′‐O‐β‐D‐glucopyranosyl‐5′‐methoxyphenyl)‐2‐methoxy‐3‐methylbenzofuran (1), 4‐methyl‐(E)‐resveratrol 3‐(2″‐p‐hydroxybenzoyl)‐O‐β‐D‐glucopyranoside (2), and 5‐O‐methyl‐(E)‐resveratrol 3‐(6″‐acetyl)‐O‐β‐D‐glucopyranoside (3), together with six known stilbenoids and phenols, acetovanillone 1‐(6′‐vanilloyl)‐O‐β‐D‐glucopyranoside, eugenyl‐O‐β‐D‐glucopyranoside, α‐(3′‐hydroxy‐5′‐methoxy‐2′‐methylphenyl)‐2‐hydroxybenzofuran, α‐(3′‐hydroxy‐5′‐methoxyphenyl)‐2‐hydroxybenzofuran, pinosilvin 3‐O‐β‐D‐glucopyranoside, and (E)‐resveratrol 3‐(6″‐galloyl)‐O‐β‐D‐glucopyranoside were isolated from the EtOH extract of the stem bark of Acanthopanax brachypus. Their structures were determined by spectral analysis including extensive 2D‐NMR spectral analyses. Compounds 2 and 3 exhibited weak cytotoxicity against human tumor A549 cell line (IC50 values of 4.87 and 5.63 μM, resp.).