The authors study three rare syndromes which are characterized by the association of cutaneous manifestations with an intestinal polyposis: Gardner's syndrome, Peutz-Jeghers-Touraine's syndrome, Cronkhite-Canada's syndrome. The Gardner's syndrome is transmitted with an autosomal prevalence, and its vital prognosis remains very porr. It is characterized by the association of various cutaneous manifestations such as fibromas, freckles, etc. with osteomas, neuro-fibromas and polyps of the large bowel. Its severity is related to the very early malignant degeneration of digestive polyps. The Peutz-Jeghers-Touraine's syndrome is transmitted in an autosomal prevalence and its vital prognosis is benign. The cutaneous manifestations are the very early occurrence of lentigines on the face, around the hiatus, and on the lips. The polyps are situated on the small bowel, and are the source of important functional phenomenons; their malignant change is rare. The Cronkhite-Canada's syndrome is rare. Its etiology is unknown and its prognosis is very poor. Its manifestation is the association of more or less wide-spread cutaneous pigmentations, alopecia, and onyxis with a digestive syndrome secondary to a pseudo-polyposis which is the origin for afecal and serous diarrhea, a cause for very severe denutrition. The diagnosis and the treatment of these three syndromes are discussed.