The Diocese of Frosinone-Veroli-Ferentino(Latin: Dioecesis Frusinatensis-Verulana-Ferentina) is a Latin Church ecclesiastical territory or diocese of the Catholic Church in Italy. It has existed since 1986. In that year, the Diocese of Ferentino was united into the Diocese of Veroli-Frosinone, which was the name of the historic Diocese of Veroli from 1956. It is immediately exempt to the Holy See and not part of an ecclesiastical province.