Guitar Hero World Tour (initially referred to as Guitar Hero IV or Guitar Hero IV: World Tour) is a music rhythm video game developed by Neversoft and published by Activision. It is the fourth main installment in the Guitar Hero series. The game was launched in North America in October 2008 for the PlayStation 2, PlayStation 3, Wii, and Xbox 360 consoles, and a month later for Europe and Australia. A version of World Tour for Microsoft Windows and Mac OS X was later released by Aspyr.

While the game continues to feature the use of a guitar-shaped controller to simulate the playing of rock music, Guitar Hero World Tour is the first game in the Guitar Hero series to feature drum and microphone controllers for percussion and vocal parts, similar in manner to the competing Rock Band series of games. The game allows users to create new songs through the "Music Studio" mode, which can then be uploaded and shared through a service known as "GHTunes".