Duke Nukem 3D is a first-person shooter video game developed by 3D Realms and published by GT Interactive Software. The full version was released for the PC (the shareware version was released on January 29, 1996). It is a sequel to the platform games Duke Nukem and Duke Nukem II published by Apogee. An expansion pack, Plutonium Pak, was released in November 1996.

Duke Nukem 3D features the adventures of the titular macho Duke Nukem (voiced by Jon St. John), who fights against an alien invasion on Earth. Along with Wolfenstein 3D and Doom, Duke Nukem 3D is considered responsible for popularizing first-person shooters. It was released to major acclaim; reviewers praised the interactivity of the environment, level design, gameplay and unique risqué humor (a mix of pop-culture satire and lampooning of over-the-top Hollywood action heroes).

Its lasting appeal and impact on modern video games has led to its being considered one of the most important video games of all time. The game's violent nature, erotic elements and portrayal of women have incited controversy. After fifteen years in development hell, a direct sequel was released called Duke Nukem Forever.