Objective: To investigate the mechanism of the effect of Linweidihuang Pills on diabetic neuropathy in rat. Methods: The diabetic rats were induced by alloxan. Serum glucose was tested by glucose oxidase and sciatic nerve sorbitol was determined by GC. Results: After Liuweidihuang Pills,0.5～2g/kg taken orally for 3 months, the level of sciatic nervous sorbitol and serum glucose in rat decreased significantly and the results showed certain dose effect relationship.Conclusion: Liuweidihuang Pills can controll diabetic neuropathy by inhibiting sorbitol biosynthesis.