Of Mice and Men is a novella written by Nobel Prize-winning author John Steinbeck. Published in 1937, it tells the tragic story of George Milton and Lennie Small, two displaced Anglo migrant ranch workers in Great Depression-era California.

Based on Steinbeck's own experiences as a bindle stiff in the 1920s (before the arrival of the Okies he would vividly describe in The Grapes of Wrath), the title is taken from Robert Burns's poem, To a Mouse, which is often quoted as: "The best-laid plans of mice and men often go awry." Required reading in many American, Australian, British, New Zealand, and Canadian high schools, Of Mice and Men has been a frequent target of censors for what some consider "offensive" and "vulgar" language; consequently, it appears on the American Library Association's list of the Most Challenged Books of 21st Century.