Tom Thumb is a character of English folklore. The History of Tom Thumb was published in 1621 and was the first fairy tale printed in English. Tom is no bigger than his father's thumb, and his adventures include being swallowed by a cow, tangling with giants, and becoming a favourite of King Arthur. The earliest allusions to Tom occur in various 16th-century works such as Reginald Scot's Discovery of Witchcraft (1584), where Tom is cited as one of the supernatural folk employed by servant maids to frighten children. Tattershall in Lincolnshire, England, reputedly has the home and grave of Tom Thumb.

Aside from his own tales, Tom figures in Henry Fielding's 1730 play Tom Thumb, a companion piece to his The Author's Farce. It was expanded into a single 1731 piece titled The Tragedy of Tragedies, or the History of Tom Thumb the Great.

In the mid-18th century, books began to be published specifically for children (some with their authorship attributed to "Tommy Thumb"), and by the mid-19th century, Tom was a fixture of the nursery library. The tale took on moral overtones and some writers, such as Charlotte Mary Yonge, cleansed questionable passages. Dinah Mulock, however, refrained from scrubbing the tale of its vulgarities. Tom Thumb's story has been adapted into several films.