Eudemus of Argos was a Greek orator and ambassador active in the first half of the 2nd century CE. His career is known solely from an honorary decree erected at Delphi, which records his successful embassy to the emperor Hadrian. He was sent by Argos to plead its case in a territorial dispute with Sparta over the region of Thyreatis, with the inscription specifically praising his oratorical skill.

No literary texts by Eudemus survive. The single work attributed to him is the oration he delivered before Hadrian, referenced in the Delphic inscription as an act of diplomatic oratory.

Eudemus exemplifies the continued practice of traditional Greek civic diplomacy under Roman imperial authority. His case highlights the enduring importance of persuasive oratory for resolving inter-city conflicts and underscores the vitality of local political engagement during the period known as the Second Sophistic.