Diodotus Tryphon is king of the Hellenistic Seleucid kingdom.

As a general of the army, he promotes the claims of Antiochus VI Dionysus, the infant son of Alexander Balas, in Antioch after Alexander's death, but then in 142 BCE deposes the child and himself seizes power in Coele-Syria where Demetrius II Nicator is unpopular for his oppressive treatment of the Jews.