Beowulf: The Monsters and the Critics was a 1936 lecture given b J. R. R. Tolkien on literary criticism on the epic poem Beowulf. First published that year in the Proceedings of the British Academy, it has been reprinted numerous times in many collections. One notable example is the 1983 collection of Tolkien's academic papers The Monsters and the Critics and Other Essays edited by Christopher Tolkien.
In the lecture, Tolkien speaks against critics who use the story solely as a source for Anglo-Saxon history. He argues that the fantasy elements of the story should be the main focus of study as they are key to the narrative. Later critics who support Tolkien's argument often cite him in their arguments.