Aldose reductase (AR), the key enzyme in the polyol pathway, plays an important role in the pathogenesis of diabetic complications such as cataract formation. AR inhibitors (ARI) can prevent or reverse early abnormalities in diabetic complications. However, none of ARI has achieved worldwide use because of limited efficacy or undesirable side effects. Therefore, evaluating natural sources for ARI potential may lead to the development of safer and more effective agents against diabetic complications. 49 Vietnam herbal medicines have been investigated with an in vitro evaluation system using aldose reductase inhibitory activities. Of these, 7 herbal medicines, Artemisia annua (leaf, stem), Duranta repens (leaf, stem), Excoecaria cochinchinensis (aerial part), Flueggea virosa (leaf, stem), Khaya senegalensis (leaf), Polygonum orientale (aerial part), Toxicodendron succedanea (leaf, stem) exhibited a significant inhibitory activity against aldose reductase. Particularly, Duranta repens (leaf, stem) and Toxicodendron succedanea (leaf, stem) showed two times more potent inhibitory activity than the positive control, 3.3-tetramethyleneglutaric acid (TMG).