The Science of Discworld (ISBN 0091886570) is a 1999 book written by novelist Terry Pratchett and popular science writers Ian Stewart and Jack Cohen. A sequel has been written to it, The Science of Discworld II: The Globe by the same authors. A second sequel, The Science of Discworld III: Darwin's Watch will be released in 2005.

The book alternates between a typical absurdistic Discworld story and serious scientific exposition. The scientific subjects center on the origins of the universe, earth and the beginnings of life. The fictional story concerns the creation of a world (the Earth) in a jar. One of the themes is that most scientific explanations commonly given are in reality a good deal more complicated.