Abstract: Four furan α-butenolactones were isolated from 50% acetone extract of tuber of Alisma orientale by silica gel column, chromatography gel column and high performance liquid chromatography techniques. Their structures were identified by modern wave spectroscopy techniques and electronic circular dichroism (ECD) and assigned as (5R)-5-hydroxy-3, 4-dimethylfuran-2(5H)-one (1), 5-hydroxy-3, 5-dimethylfuran-2(5H)-one (2), 5-hydroxy-4-(1-methylethyl)-2(5H)-furanone (3) and alismanoid A (4). Compound 1 was new compound and compounds 2–4 were first isolated from Alisma orientale. Compound 1-4 had potential antifibrotic activities.