The name Ajax can refer to:
- one of two figures in Homer's Iliad:
- Ajax the lesser King of Locris
- Ajax the great King of Salamis, a legendary hero of ancient Greece; sometimes called "Telamonian Ajax"
- Ajax, a tragedy by Sophocles
- Ajax Amsterdam, the major football team of Amsterdam
- Ajax cleanser, a trademarked line of household cleaning products made by Colgate-Palmolive
- Ajax, Ontario, Canada