Proteus syndrome is a rare, congenital hamartomatous syndrome that presents with a wide range of abnormalities. Regardless of different manifestations found in different patients, there exists three mandatory criteria for the diagnosis of this syndrome: a mosaic distribution of the lesions, a progressive course, and sporadic occurrence. When these criteria are met, the presence of additional connective tissue nevi, which are encountered mostly on the plantar surface of the feet, suffices for the diagnosis of Proteus syndrome. The authors present a 48-year-old woman who had been evaluated for a lesion on the plantar aspect of her left foot that was diagnosed as keloid and was treated unsuccessfully. In the light of the literature and with the help of histopathological reevaluation, the authors thought this unique lesion may be a localized form of Proteus syndrome.