Ovarian cystadenofibroma is a rare benign epithelial tumor whose radiological and intraoperative appearance may simulate a malignant tumor, hence the interest of our clinical case. The patient was 77 years old, multiparous, with no notable pathological history, and had presented with chronic pelvic pain. Physical examination revealed right latero-uterine tenderness with bulging in the right cul de sac. Pelvic ultrasound revealed a double tissue and fluid (mostly cystic) image in the right retro and latero uterine area, with a solid component that did not show up on color Doppler, measuring 10.5 × 5.7 cm. In addition, the uterus was of normal size with a thin endometrium and no effusion. The thoracoabdominopelvic CT scan showed a solid cystic mass probably ovarian right measuring 96 72+68 mm, otherwise no suspicious abnormality. The tumor marker CA125 was negative. A total hysterectomy with bilateral adnexectomy and multiple biopsies were performed. The postoperative course was simple. Pathological examination revealed an ovarian serous cystadenofibroma. Serous cystadenofibroma of the ovary can have a misleading appearance on imaging. It is therefore a differential diagnosis of malignant tumors of the ovary.