Chemical constituents of fruits, leaves and barks of Acanthopanax senticosus forma inermis were studied. Their fruits have higher contents of crude ash, crude protein, crude fat, fructose and glucose than those of other Acanthopanax species, and contained larger amount of glutamic acid and malic acid among amino acid and organic acid, respectively. The compounds identified from their barks and leaves, were $eta$-sitosterol and stigmasterol, sesamin, savinin, syringaresinol diglucoside, oleanolic acid, chiisanoside and polyacetytene ($C_9H_{10}O_2$, mp. 62~63).