We report a case of a 48-year-old woman with a complaint of chronic pelvic pain with a pelvic mass not related with uterus or adnexes. Preoperative ultrasonography or contrast enhanced computed tomography did not give accurate information on the origin of tumor. At laparotomy a cystic, retroperitoneal mass was totally resected without rupture. Final histopathological examination revealed that cystic spaces with abundant lymphocytes suggesting lymphangioma. No recurrence was detected in the follow up 6 months after total resection. As a result cystic lymphangioma should be considered as a rare cause of pelvic mass in women.