A 58-year-old man was referred to our hospital for investigation and treatment of a retrovesical cystic tumor that was detected during his annual health check-up. Computed tomography and magnetic resonance imaging (MRI) showed a 5 cm cystic mass including a 1.5 cm solid mass between the bladder and rectum. Transrectal biopsy was performed successfully, and did not show any evidence of malignancy. Six months later, the cystic mass enlarged, and video-assisted laparoscopic excision of the cystic mass was performed. The mass was pathologically diagnosed as a seminal vesicle cyst. Because of the rarity of this lesion, only 11 cases of laparoscopic excision have been reported and, to our knowledge, this is the first case in the Japanese literature. Under the laparoscopic prostatectomy approach, we could safely resect the lesion.