The fourth part of the world may refer to;

• The New World, also called "the fourth part of the world"
• Americae Sive Quartae Orbis Partis Nova Et Exactissima Descriptio or The Fourth Part of the World, a 1562 geographical map
• The Fourth Part of the World: The Epic Story of History's Greatest Map, a 2009 book by Toby Lester

• Johannes Schöner globe, for popularization of the term.
• Four continents
• Four corners of the world (disambiguation)
• Fourth World (disambiguation)