Archidamus IV (flourished 3rd century bc) was a king of Sparta, son of Eudamidas I, and grandson of Archidamus III. The dates of his accession and death are unknown. In 294 bc he was defeated by Demetrius I Poliorcetes of Macedonia in a battle at Mantinea, and Sparta was saved only because Demetrius I was called away by the threatening activities of a rival Lysimachus and Ptolemy II.