The simultaneous occurrence of neurofibromatosis and a peripheral neuropathy that has the clinical and electrophysiological features of Charcot-Marie-Tooth disease (HMSN I) has rarely been reported. A recent report described patients with HMSN I with hypertrophic lumbosacral nerve roots. We report a patient with compelling evidence for neurofibromatosis who also demonstrates clinical and electrophysiological features of Charcot-Marie-Tooth disease. Abdominal and pelvic CT scan revealed diffusely and symmetrically enlarged lumbosacral nerve roots. These nerve roots were biopsied, and the specimens revealed neurofibromas. Histology, electrophysiological studies, radiology, and clinical appearance of the abnormality in peripheral nerves and lumbosacral nerve roots will be emphasized in this paper. The simultaneous occurrence in our patient of neurofibromatosis and Charcot-Marie-Tooth disease suggests a possible genetic relationship between these two disorders.