Nine cases of Olmsted syndrome have been reported in the world literature. In this syndrome, keratoderma usually starts during infancy on the palms and soles when the baby starts to use the feet for walking and the hands for grasping. Within weeks or months, there is progressive spread of solid, symmetrical, thick hyperkeratotic keratoderma to both palms and soles, surrounded by erythematous margins. Contraction of fingers and deep fissuring of the feet are common complications. Symmetrical, yellow-brown hyperkeratotic plaques and papules are also observed around body orifices such as the mouth, nares, inguinal region, and perianal and gluteal areas. Other clinical manifestations have been reported, including diffuse alopecia, thin nails, leukokeratosis of the oral mucosa, onychodystrophy, hyperkeratotic linear streaks, exaggerated keratosis pilaris, and large verrucous plaques in the axillae. In the differential diagnosis, other keratoderma and hyperkeratotic syndromes should be considered.