A 48-year-old man presenting with perineal pain, weak stream and dysuria was found to have a Cowper's gland duct cyst measuring 1.8 x 3.5 cm, which was investigated with retrograde and voiding urethrography, cavernosography and perineal MRI, which was the single most useful imaging technique. Treatment consisted in complete surgical excision, which allowed an anatomical reconstruction of the urethra. This condition is typical of the pediatric age group, and seldom diagnosed in adults.