World 9-4

World 9-4 may refer to:
 * World 9-4 (New Super Mario Bros. Wii)
 * Hammerswing Caverns, World 9-4 of New Super Mario Bros. U
 * Hammerswing Hangout, World 9-4 of New Super Luigi U
 * Creepy-Crawly Bowser Tower, World 9-4 in Super Mario Maker.