Dispersed endometrium tissue can be observed in 10% of all laparotomies. In some rare instances the endometriosis also appears within the region of the intestinal canal. It is reported on a 48 year old woman observing diarrhoea tinged with blood at four weekly intervals. With the clinical picture of a mechanical ileus she was admitted to hospital. In the laparotomy a big stenosing sigmoidotumor showing histological endometriosis seats was found.