Created suffragan of the Archdiocese of Lipa, separating from the Mother Diocese of Lucena on 2 April 1977, it has jurisdiction over the province of Marinduque.

The Jesuits in the Philippines 1581–1768, a book written by Horacio de la Costa, states that Archbishop Miguel Garcia Serrano of Manila entrusted the island of Marinduque to the care of the Society of Jesus in 1621.

By virtue of a Spanish royal decree dated 19 May 1864, the Augusti-nian Recollect Fathers took over the spiritual administration of Boac in exchange for the curacies they left behind to the hands of the Jesuit missionaries in Mindanao.

Before the creation of the Diocese of Lipa by Pope Pius X, the island of Marinduque, since 14 August 1595 till 10 April 1910, belonged to Archdiocese of Manila.

On 10 May 1978, carried by the effect of the papal bull, the Diocese of Boac was canonically erected according to the Decretum Executorium signed by Bruno Torpigliani, the Apostolic Nuncio to the Philippines.