Actua Pool is a sports simulation video game developed by British company Gremlin Interactive as part of their highly successful Actua Sports series of sport simulators of the mid-to-late 1990s. Actua Pool, a pool (pocket billiards) was originally released on the Microsoft Windows platform and the Sony PlayStation home console in 1999; these versions were also published under the name Pool Shark. The game was very well received, praised for its realistic physics engine and challenging AI opponents, although the game spawned a sequel which was not as successful. In 2007, Actua Pool was ported to the Nintendo DS handheld game console, under the title Underground Pool in North America.

Actua Pool is a pool simulation game with dozens of game modes, including eight-ball, nine-ball, three-ball, ten-ball, killer rules, cutthroat rules, bank rules, speed pool, one-pocket, various foreign styles and traditional snooker rules. There are dozens of venues, unique individual opponents and even different-shaped and unique tables are also available to unlock.

In one player mode, called "Hustle Mode", the character must hustle your way through smoke filled bars, casinos, pool halls and nightclubs and aim to black ball up to 18 challengers of ever-increasing skill across a range of challenging tables. There is an interactive tutorial if the player wishes, and the player can learn hundreds of trick shots from the tutorial. Each individual NPC opponent has its own unique appearance, voice, mannerisms, playing style and difficulty, and winning tournaments unlocks new NPCs to play against and venues to play in. The last opponent is the Devil himself, who you will play in Hell on his very own pool table and play for your very soul.

There are also the traditional two-player modes, as well as three-player, four-player, and so on. Any number of players can join in, and tournaments for up to 16 players are also available in which the NPC's can also be included. Player characters are completely customizable, and stats (such as accurracy and shots potted) tally up an individual player's ability.