Ganglioneuroma is a rare benign tumor. It is the most mature of neurogenic tumors. We report a case of a pelvic ganglioneuroma diagnosed in 24-year-old pregnant woman who presented with an urinary infection. Echographic examination suggested an ovarian mass. At surgical operation, the tumor was close to the sacrum. A total resection of the tumor was performed. Pathological examination proved it as a ganglioneuroma. Sixteen months later, the patient is free from disease.