The presence of a benign pelvic mass, ascites, and an elevated CA 125 tumor marker level may mimic the presentation of ovarian adenocarcinoma. Two cases of ovarian cellular fibromas are reported to illustrate that the presence of ascites in association with an elevated CA 125 serum level may mislead physicians into a diagnosis of ovarian carcinoma. Although CA 125 is helpful for following patients after ovarian carcinoma has been diagnosed histologically, it has limited value as a screening test. Exploratory laparotomy with excision of the pelvic mass remains the only reliable and acceptable method available to achieve an accurate diagnosis.