Diabetic muscle infarction is a rare complication of diabetes mellitus first described in 1965. It typically arises in patients with long-standing diabetes mellitus who have complications of the disease, including nephropathy, retinopathy, and neuropathy. It typically presents with acute onset of thigh pain with an associated palpable tender mass. Recurrent episodes in the same or opposite limb are common. Laboratory evaluation does not generally show any consistent abnormality except for poor glucose control. Histologic features of diabetic muscle infarction consist of large areas of muscle necrosis and edema. Magnetic resonance imaging (MRI) findings in patients without clinical evidence of infection may be typical enough to make tissue biopsy unnecessary. In the appropriate clinical setting, MRI may obviate invasive testing and is the preferred imaging modality. Treatment is supportive with analgesics, rest, and immobilization.