Sub Battle Simulator is a naval combat simulation computer game released by Epyx in 1987. The game was developed by Digital Illusions, Inc. It was released on several platforms, including the Amiga, Apple II, Apple IIGS, Commodore 64, Atari ST and IBM-compatible PCs.
Sub Battle Simulator sets the action in times of World War 2, with the player on the American or German side. There are 60 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.
Game reviewers Hartley and Pattie Lesser complimented the game in their "The Role of Computers" column in Dragon #122 (1987), calling it "the finest of the submarine simulation games" and stating "This is a real winner for wargaming enthusiasts!"