Giulio Cesare Sacchetti (1586 – 28 June 1663) was an Italian Catholic Cardinal and was twice included in the French Court's list of acceptable candidates for the Papacy, in 1644 and 1655.
Sacchetti was born in 1586, the second surviving son of Giovanni Battista Sacchetti and Francesca Altoviti, both Florentine patricians who had moved to Rome in the late sixteenth century. Giulio was the uncle of Cardinal Urbano Sacchetti.
Sacchetti's father was a trading partner of the Barberini family of Pope Urban VIII and the two families became close. Sacchetti's elder brother, Marcello Sacchetti, became papal treasurer to Pope Urban VIII and a prominent patron of the arts until his death in 1629.
Sacchetti was educated at the University of Perugia and the University of Pisa. On 10 Dec 1623, he was consecrated bishop by Agustín Spínola Basadone, Bishop of Tortosa, with Ottavio Accoramboni, Archbishop Emeritus of Urbino, and Diego Merino, Bishop of Montepeloso, serving as co-consecrators, and elected Bishop of Gravina.
Sacchetti was papal nuncio to Madrid from 1624-1626. His service in the Spanish Nunciature and ties to the new pope ensured his becoming a cardinal only two years after his consecration. He was elevated to the cardinalate by Pope Urban VIII on 19 January 1626, and named Cardinal-Priest of Santa Susanna. He was appointed papal legate to Ferrara from 1627 to 1631, and to Bologna from 1637 until 1640.