Salviati was born in Florence to Jacopo Salviati, son of Giovanni Salviati and Maddalena Gondi, and Lucrezia di Lorenzo de' Medici, elder daughter of Lorenzo de' Medici. Pope Leo X, who raised him to the cardinalate in 1517, was Lorenzo's son, and therefore Giovanni's uncle. His brother Bernardo Salviati and nephew Anton Maria Salviati also became cardinals. He was also Cousin of Catherine de' Medici from whom he derived patronage.
He held many posts. He was protonotary apostolic, bishop of Porto e Santa Rufina, and sub-dean of the Sacred College of Cardinals. In 1526 signed for the Pope the League of Cognac against Charles V. He became Bishop of Albano in 1543. He was appointed Administrator of Oloron Diocese in 1520. and attended the Papal conclave of 1549–50 as a cardinal.
He was on friendly terms with Machiavelli, writing to him. The artist Cecchino Salviati (Francesco de' Rossi) took the name Salviati from Giovanni, who was his patron. He employed the composer Jacques du Pont.
Salviati died at Ravenna October 28, 1553.