A 2-year, 6-month-old boy with peritoneal pseudomyxoma had a hamartomatous Peutz-Jeghers-like polyp in the gall-bladder. The morphological pattern of the polyp was very characteristics of what is usually considered an hamartomatous polyp. The patient presently reported has no clinical characteristics of Peutz-Jeghers syndrome. The peritoneal pseudomyxoma creates differential diagnostic problems with well-differentiated mucinous adenocarcinoma.