Francesco Maria Piccolomini (died 1599) was a Roman Catholic prelate who served as Bishop of Montalcino (1554–1599) and Bishop of Pienza (1563–1599).^[1][2][3]

On 20 April 1554, Francesco Maria Piccolomini was appointed during the papacy of Pope Julius III as Bishop of Montalcino.^[1][4][5] On 25 November 1554, he was consecrated bishop by Scipione Bongalli, Bishop of Civita Castellana e Orte, with Cesare Cibo, Archbishop of Turin, and Alessandro Piccolomini, Bishop of Pienza, serving as co-consecrators.^[4] In December 1563, he was appointed during the papacy of Pope Pius IV as Bishop of Pienza.^[1][4] He served as Bishop of Montalcino and Bishop of Pienza until his death in 1599.^[1][2][3][4]

While bishop, he was the principal co-consecrator of:^[4]

• Giovanni Antonio Locatelli, Bishop of Venosa (1568);
• Cipriano Pallavicino, Archbishop of Genoa 1568); and
• Ascanio Piccolomini, Titular Archbishop of Colossae and Coadjutor Archbishop of Siena (1579).