Bug! is a platform game developed by Realtime Associates and published by Sega for the Sega Saturn. It was first released in North America, in 1995, weeks after the Saturn's launch there; in Europe on September 15, 1995; and, in Japan, on December 8 the same year. It was also ported to Windows 3.1x and Windows 95 in 1996 by Beam Software. The game is one of the earliest examples of 3D platforming, as well as one of the first platform games released on the Saturn. Character movement is restricted to a track, unlike many in the genre that allow for unrestricted movement in all directions.

The game centers around Bug, a green bug – and Hollywood actor – who hopes to gain fame by defeating the villainous Queen Cadavra. The game was developed with the titular character being considered a possible mascot for the Saturn. Although Bug! failed to capture consumers' attention, it received positive reviews upon its release. Critics praised its graphics and colorful visual effects, but the game's music and voice acting were criticized.

A sequel, Bug Too!, was released for the Saturn in 1996.