He was brother of Gabrio (condottiero and general) and Giovan Battista (castellan of Castel Sant'Angelo and later Bishop of Cassano all' Ionio).

Living in Rome near the Pope, he was appointed bishop of Novara on 13 March 1560[4] and Legate (i.e. governor) of Camerino in 26 April 1560.

After the death of Pius IV in 1565, he was appointed governor of Città della Pieve in place of Camerino, an office he held till 1570.

In his life he changed many cardinal titles before being appointed Cardinal bishop: on 17 May 1565 he was appointed Cardinal-priest of Santa Maria degli Angeli, a church he helped to build and where he and Pope Pius IV were buried; on 12 April 1570 he passed to San Pietro in Vincoli, on 9 June 1570 to San Clemente, on 3 July 1570 to Sant'Angelo in Pescheria, on 31 July 1577 to Santa Maria in Trastevere.

Giovanni Antonio Serbelloni died in Rome on 18 March 1591 and was buried in Santa Maria degli Angeli.