This project is to investigate lignans from the seed of Hydnocarpus anthelminthica. Thirteen lignans were isolated from the 95% ethanol extract of the seed of H. anthelminthica, by polyamide resin, Sephadex LH-20, ODS column chromatography and preparative HPLC. Their structures were elucidated as(+)-syringaresinol(1), lirioresinol A(2),(+)-medioresinol(3),(7R,8R,8'R)-4'-guaiacylglyceryl-evofolin B(4), leptolepisol C(5),(-)-(7R,7'R,7″R,8S,8'S,8″S)-4',4″-dihydroxy-3,3',3″,5,5',5″-hexamethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineolignan-7″,9″-diol(6),(-)-(7R,7'R,7″R,8S,8'S,8″S)-4',4″-dihydroxy-3,3',3″,5,5'-pentamethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'ses-quineolignan-7″,9″-diol(7), ceplignan(8), hydnocarpusol(9), isohydnocarpin(10),(-)-hydnocarpin(11), hydnocarpin(12), and hydnocarpin-D(13) by spectroscopic data analysis. Compounds 1-8 were obtained from the genus Hydnocarpus for the first time.