A 53-year-old female visited our hospital with a complaint of acute urinary retention. Transvaginal ultrasonography, computed tomography and magnetic resonance imaging showed extreme thickening of the urethral wall. Histopathological examination of the transvaginal needle biopsy suggested well-differentiated adenocarcinoma. She underwent total cysto-urethrectomy with partial vaginal wall resection and ileal conduit urinary diversion. Pathological diagnosis of the tumor was columnar adenocarcinoma invading into the vaginal wall and periurethral connective tissue. Fifty-eight cases of primary adenocarcinoma of the female urethra in the Japanease literature are briefly reviewed.