Cerbonius (Latin: Cerbo; Italian: Cerbone, Cerbonio; died 575 AD) was a bishop of Populonia during the Barbarian invasions.

Due to persecution by the Arian Vandals in North Africa, the local Christian community dispersed, and together with Regulus, Felix, and some priests, Cerbonius escaped to Italy.

The citizens soon became frustrated with him, however, since Cerbonius rose every Sunday at daybreak and said mass instead of doing so at the normal hour.

Vigilius, on hearing what Cerbonius had done, became angry and sent legates to Piombino to bring the bishop to Rome.

During the way, he cured three men suffering from fever and tamed some wild geese by making the sign of the cross over them, which explains this particular attribute.

The ship carrying his body ran into a heavy storm, but arrived safely at Populonia.

A local proverb states: Chi non beve a San Cerbone - è un ladro o un birbone ("Whoever does not drink from the fountain of Saint Cerbonius – is a thief or a rascal.").