Three new arylnaphthalide lignans, 5-(4-hydroxy-3-methoxyphenyl)furo[3',4':6,7]naphtho[2,3-d]-1,3-dioxol-6(8H)-one (1), 10-(4-hydroxy-3-methoxyphenyl)furo[3',4':6,7]naphtho[1,2-d]-1,3-dioxol-9(7H)-one (2), and 10-(3,4-dimethoxyphenyl)-6-hydroxyfuro[3'.4': 6,7]naphtho[1,2-d]-1,3-dioxol-9(7H)-one (3), together with two known ones. chinensin (4) and isodiphyllin (5), were isolated from the aerial parts of Bupleurum marginatum WALL. ex DC. The structures of the three new lignans were established by means of NMR spectroscopic studies, including HQSC, HMBC, and ROESY.