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Diabetic foot ulcers are an important clinical problem, leading to infection and loss of limb [1]. Diabetic foot ulcers occur in 15% of patients with diabetes mellitus, with a yearly incidence of 1%–2% [2]. Diabetic patients have higher rates of hospitalization for skin and soft-tissue infections than patients without diabetes [3]. Most studies based on culture have shown that the infections are polymicrobial, with Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus species (especially Staphylococcus aureus) being the most prevalent isolates [4, 5]. Traditionally, the pathogenesis of these wounds has been attributed to factors such as neuropathy (a functional disturbance in peripheral nerves), repeated trauma, and peripheral vascular disease [6]. More recently, the roles of wound bioburden and functionally equivalent pathogroups in diabetic wound infections have been studied [7, 8]. Data on the composition of the cutaneous microbiota of diabetic patients is lacking. One of the few studies to address this question was performed in 1975, in the era prior to high-throughput 16S rRNA sequencing (HTS) technology [9]. No differences in culturable organisms between control and diabetic skin were found, but the study also did not examine the feet. Staphylococcus species account for 70% of the normal skin microbiome on the plantar aspect of the foot [10, 11]; most are coagulase-negative Staphylococcus species that are of low virulence and may compete with the more virulent S. aureus [12]. In contrast, on intact skin on the contralateral (opposite) limb of patients with unilateral diabetic ulcers, only 7% of the microbiota was represented by Staphylococcus species [13], suggesting a loss of these protective organisms or their replacement by other species. HTS identification based on deep sequencing is currently being used to better characterize the human microbiome [14, 15]. We sought to use HTS along with quantitative polymerase chain reaction (qPCR) to better characterize the microbiota of the diabetic foot. The aim of this study was to determine whether there are differences in surface microbiota of the arm and foot between nondiabetic men and diabetic men without a history of diabetic foot ulcer.