Ottavio Accoramboni (1549 – 23 May 1625) was a Roman Catholic prelate who served as Archbishop of Urbino (1621–1623), Apostolic Nuncio to Portugal (1614–1620), and Bishop of Fossombrone (1579–1610).

[1] His younger sister, Vittoria, married in 1573 Francesco Peretti, a nephew of Cardinal Montalto, who supported the ecclesiastic career of Ottavio.

[5] The other main effort of Ottavio was to defend the interests of the Church and in particular he opposed the law that required a permit of the king for the ecclesiastics to buy real estates.

To sanction violations of the Church's jurisdiction, on 27 June 1617 he imposed a general interdict in Portugal, which was left only on 30 May of the following year after the intervention of Rome.

[5] On 4 June 1620 Vincenzo Landinelli was appointed as Nuncio in his place,[4] but Ottavio remained in Portugal until the end of 1622.