Following a broad review of the rarity and unusual nature of the condition, two cases of mesenteric cysts are reported. The first was seen in a girl in whom onset involved a picture of acute intestinal occlusion secondary to the development of mesenteric cyst. This was treated by demolition surgery because of the cyst's close links with adjacent structures. The second cases was seen in a woman. In this case it was possible to remove the cyst conservatively. In the light of experience also, anatomo-clinical study of the cases forms the basis for some conclusions on the pathogenetic problem of mesenteric on the pathogenetic problem of mesenteric cysts, congenital or acquired expressions of lymphatic flow decompensation.