Palladius (c. 420 – June 455) was Caesar of the Western Roman Empire for two months in 455, together with his father Petronius Maximus.
According to Hydatius, he was a son of Petronius Maximus from a previous marriage. In the second half of the 430s, he could have been a praetor.
In March 455 his father become Emperor after the death of Valentinian III. Petronius appointed Palladius Caesar and had him marry Eudocia, the elder daughter of Valentinian. However, Eudocia had been betrothed to Huneric, son of the King of the Vandals Genseric, who retaliated sacking Rome. Petronius died stoned by an angry mob (April 455), a fate probably shared by Palladius.