Some known coumarins, decursin, nodakenetin, umbelliferone, 7-demethylsuberosin, columbianetin, decursinol angelate and decursinol, showing significant cytotoxic activities against P388 cell lines,were isolated from the roots of Angelica gigas (Umbelliferae) . 7-Demethylsuberosin and columbianetinwere obtained from Angelica gigas for the first time. Chernotaxonornic difference about coumarins com-ponents between the roots of Angelica gigas and those of A. acutiloba is also discussed.