Although there have been a few reports of cases in which cancer cells of extrauterine origin were observed in vaginal smears, such findings are relatively uncommon. We recently experienced a case of ovarian serous cystadenocarcinoma diagnosed by cervicovaginal smear in a 56-year-old woman in routine work-up of carcinoma peritonei. The cellular features were several scattered cellular clusters of adenocarcinoma cells in clear background without tumor diathesis. Psammoma body was not present. Exploratory laparotomy confirmed the diagnosis of bilateral ovarian serous cystadenocarcinoma with multiple metastases.