Giacomo Savelli (1523–1587) was an Italian Roman Catholic cardinal and bishop.
A member of the Savelli family, Giacomo Savelli was born in Rome in 1523, the son of Roman nobles Giambattista Savelli and Costanza Bentivoglio. His paternal grandmother, Camilla Farnese, was a cousin of Pope Paul III.
Savelli studied Latin and Greek as a young man and then attended the University of Padua to study law. He joined the papal household of Pope Paul III as a chamberlain of honor. He also served as a protonotary apostolic.
Pope Paul III made him a cardinal deacon in the consistory of December 19, 1539. He received the red hat and the deaconry of Santa Lucia in Selci on April 16, 1540. On January 8, 1543, he opted for the deaconry of Santi Cosma e Damiano. From April 13, 1545 to May 26, 1546, he was the administrator of the see of Teramo.
He participated in the papal conclave of 1549-50 that elected Pope Julius III. The new pope made Cardinal Savelli papal legate in the March of Ancona and he served in that position throughout the pontificate of Julius III. He opted for the deaconry of San Nicola in Carcere on March 9, 1552.