Callixenus or Kallixenus or Kallixenos may refer to:
Kallixenos, nephew of Cleisthenes and head of the Alcmaeonids, ostracised 485 BC
Callixenus, Athenian politician who aggressively prosecuted those held to be to blame for the disaster at the Battle of Arginusae in 406 BC
Callixenus of Rhodes, Hellenistic historian, main source for the Tessarakonteres