We examined methanol extracts prepared from the Korean plants for their inhibitory effects on rat lens aldose reductase (RLAR) activity in vitro. Among 41 plant extracts, the extracts of Lagerstroemia indica, Punica granatum, Eurya japonica, Liquidambar styraciflua, and Vitis coignetiae exhibited highest inhibitory potency, even more potent than tetramethylene glutaric acid (TMG), known as one of typical aldose reductase inhibitors $(IC_{50};value,;0.51;{mu}g/ml)$. Especially, the extract of Lagerstroemia indica (Lythraceae), exhibited the most inhibitory potency $(IC_{50};value,;0.069;{mu}/ml)$ on RLAR.