Diabetes is now considered one of the main threats to human health in the 21st century and many researchers are dedicated to investigate the physiopathology of the disease, with further insights on the managements of its major complications. Since understanding the pathophysiology of the major complications of diabetes and their underlying processes is mandatory, experimental models of the disease may be useful as they allow the recognition of the early mechanisms involved in the long-term complications of diabetes. Peripheral nerve involvement is highly frequent in diabetes mellitus and it has been documented that one third of diabetic patients have peripheral neuropathy. The true prevalence is not known and reports vary from 10% to 90% in diabetic patients, depending on the criteria and methods used to define neuropathy. In this review, the most common experimental models of diabetes are presented and the pathological findings on major peripheral nerves are discussed. Also, the insights brought by morphometry to the diabetic neuropathy research are highlighted.