Two triterpenoids (1,4) and two triterpenoid glycosides (2,3) were isolated from the root of Acanthopanax koreanum (Araliaceae). Their structures were identified as impressic acid (1), acankoreoside A (2), 3-epi-betulinic acid 28-O-［(${alpha}-L-rhamnopyranosyl(1{ ightarrow}4)-{eta}-D-glucopyrano-syl(1{ ightarrow}6)]-{eta}-D-glucopyranosyl]$ ester (3), and ursolic acid (4) by physicochemical and spectro-scopic methods. Of these compounds, impressic acid (1) exhibited a potent inhibitory activity against NFAT transcription factor ($IC_{50}:{;}12.65{;}{mu extrm{m}}$).