A broad spectrum of cutaneous disorders may be encountered in patients with both type 1 and type 2 diabetes mellitus. On occasion, these dermatologic findings may even precede any clinical or biochemical evidence for diabetes. Cutaneous manifestations of diabetes mellitus can be classified as conditions with strong associations with diabetes mellitus; infectious causes of skin lesions; dermatologic disorders related to complications of diabetes mellitus; and skin conditions related to the treatment of diabetes mellitus. This article provides a concise review of the epidemiology, clinical findings, histopathologic features, differential diagnostic considerations, and therapeutic approaches to specific dermatologic disorders seen in diabetic patients. This article also provides a framework for an effective approach to the majority of cutaneous manifestations encountered in patients with diabetes mellitus in a typical primary care setting.