Paratubal cysts may mimic ovarian cysts, and most of them are diagnosed postoperatively. They originate from the mesosalpinx between the ovary and the fallopian tube. Only a few are large, and most paratubal cysts are less than 10 cm. We report a huge paratubal cyst in a 30-year-old woman, whose only preoperative complaint was abdominal distention over 4 months. Conservative surgery was performed with cyst removal while preserving the ovaries and tubes. A paratubal cyst should be included in the differential diagnosis of a large pelvic masses, especially in the reproductive age.