A new veratramine-type alkaloid (1), along with 4 known compounds (2-5), was isolated from the roots of Veratrum maackii var. jeponicum (Baker) T. Shimizu. Their structures were elucidated on the basis of NMR and mass spectroscopic data. All compounds were evaluated for their antioxidant activities using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+)) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Compounds 1 and 3-5 showed ABTS + radical scavenging activity with IC50 values ranging from 15.0 to 85.7 mu M.