Diabetic peripheral neuropathy is one of the most common complication of diabetes, which causes pain and inconvenience to the patients and reduces the quality of life. The pathogenesis of DPN is not yet clear, which is the result of multi-factor interaction. Hyperglycemia is clearly an important factor for its pathogenesis and development. Several metabolic pathways have been identified that may relate to the cellular metabolic including glucose flux through the polyol pathway, the hexosamine pathway, production of the protein kinase C isoforms and accumulation of advanced glycation end products. The additive imbalance of these pathways alters the mito-chondrial redox state of the cell and results in oxidative stress. It also causes inflammation. Additionally, growth factors, insulin resistance and lipid abnormality may participate in the metabolic pathway. This review is aimed to elaborate the pathogenesis and complement the known mechanism.