The Diocese of Pienza (Latin: Dioecesis Pientinus) was a Roman Catholic diocese located in the town of Pienza in the province of Siena, in the Val d'Orcia in Tuscany between the towns of Montepulciano and Montalcino. In 1772, it was suppressed and united with the Diocese of Chiusi to form the Diocese of Chiusi e Pienza.
Erected: 13 August 1462
Latin Name: Pientinus
Giovanni Chinugi (7 Oct 1462 - 30 Sep 1470 Died)
Tommaso della Testa Piccolomini (26 Oct 1470 - 1482 Died)
Agostino Patrizi de Piccolomini (19 Jan 1484 - 1495 Died)
Francesco Todeschini-Piccolomini (31 Oct 1495 - Mar 1498 Resigned)
Girolamo Piccolomini (senior) (14 Mar 1498 - 1510 Resigned)
Girolamo Piccolomini (junior) (9 Dec 1510 - 1535 Died)
Alessandro Piccolomini (1535 - Dec 1563 Resigned)
Francesco Maria Piccolomini (Dec 1563 - 1599 Died)
Gioia Dragomani (15 Dec 1599 - 26 Dec 1630 Died)
Scipione Pannocchieschi d'Elci (28 Jul 1631 - 3 Mar 1636 Appointed, Archbishop of Pisa)
Ippolito Borghese, O.S.B. (1 Sep 1636 - Mar 1637 Died)
Giovanni Spennazzi (5 Oct 1637 - 11 Aug 1658 Died)
Giacondo Turamini (31 Mar 1664 - 17 Jan 1665 Died)
Giovanni Checconi (11 Nov 1665 - 19 Mar 1668 Died)
Girolamo Borghese, O.S.B. (17 Dec 1668 - 15 Jan 1698 Died)
Antonio Forteguerra, O.S.B. (15 Sep 1698 - Jan 1714 Died)
Ascanio Silvestri (13 Jun 1714 - Nov 1724 Died)
Cinugo Settimio Cinughi (18 Apr 1725 - Mar 1740 Died)
Francesco Maria Piccolomini (3 Jul 1741 - 27 Jan 1772 Resigned)
15 June 1772: United with the Diocese of Chiusi to form the Diocese of Chiusi e Pienza
