The most common cause of vesicovaginal fistula in developed countries is iatrogenic injury whereas in developing countries the leading cause is obstetric complications. Spontaneous vesicovaginal fistula is extremely rare. In this case report, a 23-year-old female patient with moyamoya disease and a stable right ovarian cyst and a vesicovaginal fistula without any underlying factor is discussed. She was fully continent. If there is any possible relationship between vesicovaginal fistula and moyamoya disease, it needs further investigations.