Aldose reductase (AR) plays a central role in the development of the diabetic complications. Eighty one Korean herbal medicines have been investigated for inhibitory activities on AR. Among them, fourteen herbal medicines exhibited a significant inhibitory activity compared with 3,3-tetramethyleneglutaric acid (TMG) as positive control. Particularly, Xanthium strumarium (fruit, whole plant), Ilex cornuta (stem and leaf), Vitex rotundifolia(stem), Sophora flavescens (whole plant), Platycarya stobilacea (flower) showed two times more potent inhibitory activity than 3,3-tetramethyleneglutaric acid (TMG).