Arnor is a fictional kingdom in J. R. R. Tolkien's writings. Arnor, or the Northern Kingdom, was a kingdom of the Dúnedain in the land of Eriador in Middle Earth. The name probably means "Land of the King", from Sindarin Ara- (high, kingly) + (n)dor (land). Arnor is the territory of Middle-earth associated with the High Kings of the line of Elendil, the kingship of which was restored at the crowning of Elessar (Aragorn) after the War of the Ring at the start of the Fourth Age.

Arnor may refer to:

• Arnor Angeli, Belgian football player
• Arnór Guðjohnsen, Icelandic football player
• Arnór Hannibalsson, Icelandic philosopher, historian and translator
• Arnór Ingvi Traustason, Icelandic basketball player
• Arnor Njøs, Norwegian soil researcher
• Arnor Sighvatsson, Icelandic economist
• Arnór Smárason, Icelandic football player
• Arnór Sveinn Aðalsteinsson, Icelandic football player
• Arnórr jarlaskáld, Icelandic Skald
• Einar Arnórsson, Minister for Iceland
• Jón Arnór Stefánsson, aIcelandic basketball player