A 6-month-old dead fetus, removed from the uterus of a 4-year-old Holstein cow, was referred to our department. A fluctuant sac, approximately 25x20x30 cm, covered with skin was observed over the occipital region of the cranium. Almost 4 liters lucid liquid was discharged from the sac. After the dissection of the soft tissue, a 1 cm diameter hole with irregular edges in connection with extracranial sac was determined on top of the occipital region of the left hemisphere in the cerebrum. The subject was diagnosed as meningoencephalocele due to the existence of prolapsed cerebellum in the sac. Also, a second channel connecting the fourth ventricle into the sac was also determined via MR images. An occipital meningoencephalocele in a 6-month-old holstein fetus was defined in this case report by pathologic-anatomic and radiological diagnosis.