Background:Olmsted syndrome is a rare keratinization disorder characterized by a combination of periorificial keratotic plaques and bilateral palmoplantar transgredient keratoderma. Other clinical manifestations include diffuse alopecia, leukokeratosis of the oral mucosa, onychodystrophy, hyperkeratotic linear streaks, follicular hyperkeratosis and constriction of digits.Main observations:We report a case of Olmsted syndrome in a 5-year-old male presented by mutilating palmoplantar keratoderma, perioral keratoses and linear hyperkeratotic lower limb plaques.Conclusions:Olmsted syndrome is a rare genodermatosis with only 43 cases reported so far. We present another case of the disease.