Eudamidas I (Greek: Εὐδαμίδας) was Spartan king between 331 and c. 300 BC. He succeeded his brother Agis III, who died at the battle of Megalopolis against Macedonia. Eudamidas' reign was therefore peaceful as Sparta recovered from this disaster. He even refused to join the other Greek states in the Lamian War in 323, and was later noted for his interest in philosophy—peculiar for a Spartan king.