A rare case of extrapelvic endometriosis occurring at the hepatic lobe. Only 17 cases of hepatic endometriosis have been discussed in literature. A 43 year old woman with extrapelvic endometriosis, in which initial diagnostic workup suggested hepatic lob cyst. An operation revealed the large cystic mass to be contiguous to the normal liver parenchyma. Histologic evidence obtained from exploratory laparotomy showed irregular proliferation of endometrial glands and stroma, as well as normal ovarian tissue, which led to the final diagnosis of endometriotic cyst in an ectopic ovary. Endometriosis should be considered as a differential diagnosis in female patients presenting with an abdominal cyst/mass.