Sub Battle Simulator is a naval combat simulation game released by Epyx in 1987. The game was developed by Digital Illusions, Inc. It was released for the Amiga, Apple II, Apple IIGS, Commodore 64, Atari ST, Macintosh, MS-DOS, and the Tandy Color Computer 3.

Sub Battle Simulator sets the action in times of World War 2, with the player on the American or German side. There are 36 German missions and 24 American missions in which the player can command six different submarines. The player is responsible for navigation, using five different levels of mapping, attacks' planning based on weather and surroundings as well as paying attention to the radar. The game gives the possibility to play underwater or on the surface. A player can choose target practice, individual missions or war commands as either a German or an American submarine Captain.