Context: Paraneoplastic cerebrall degeneration is a rare neurological syndrome, in most cases associated with the presence of anti-Yo antibodies. Diagnosis is based on symptoms – moderate cerebral failure symptoms (> = 3 Rankin score) lasting at least 12 weeks with no evidence of cerebrall atrophy in MR scan. Results: We report the case of 65 year old women with dysarthria, impaired coordination, dizziness and dysphagia, with normal MR scan. We found serum anti-Yo antibodies and multilocular tumor in the left ovary in ultrasound scan. In the preoperative period the patient demonstrated decreasing levels of consciousness. The patient was treated with total hysterectomy with bilateral salphingo-oophrectomy and limphadenectomy. Histological examination of ovarian cancer tissue confirmed the presence of anti-YO antibodies in the tumor. The immunohistochemical staining revealed a strong granular staining pattern of Yo protein in the nucleus. The Yo protein expression was found in the tumor cells, as well as in the tumoral stroma and epithelial cells. During the two-weeks follow up we observed a weak improvement of cognitive function. Conclusions: Normal MR scan accompanying cerebellar syndrome supports a suspicion of paraneoplastic syndrome and should lead to causative treatment.