The military in GTA games are the armed forces of the USA, comprising mostly of the Army, but also with air and naval bases. The army themselves don't appear in Grand Theft Auto IV, because it enhances realism - the army would not be sent to kill one person, and also because the army do not generally operate within large cities. The army is replaced somewhat by NOOSE. The military is also important in many missions throughout the series, such as Sir, Yes Sir!, Black Project, Green Goo, Up, Up and Away!, Vertical Bird and Over the Top.
After the player gains six stars in a GTA III Era game, the army will begin to chase the player. On the ground, two military vehicles are used to kill the player; the Barracks OL, which is used for troop transport, and the Rhino tank. The soldiers themselves are always well armed with weapons that will often make short work of the player and most vehicles.
Members of the military behave as a gang in Vice City and will attack the player if spotted on military territory, unless in a Cop uniform. They will also set up roadblocks comprised of the Barracks OL with soldiers armed with m16's in GTA III, M4's (in Fort Baxter Air Base) and MP5's (during a 6-star wanted level), and M4 Carbines in every other GTA III Era game. These aren't as lethal as those of the FBI since there could be two FBI vehicles taking up one road with at least eight agents. But seeing as how the Barracks takes up the space of one road they can be broken through although the MP5s still pose a threat, especially since the Army is very well trained, more than the FBI.
A strange thing is that soldiers in the Fort Baxter Air Base never participate in law enforcement activity; if the player is wearing a police uniform or army fatigues and enters the base with a wanted level; only the law enforcement officers that enter from outside will try killing the player.
- Fort Baxter Air Base in Vice City Mainland, Vice City.
- United States National Guard Depot in Ocean Docks, Los Santos, San Andreas.
- Easter Basin Naval Station in San Fierro, San Andreas.
- Area 69 in Bone County, San Andreas.
- K.A.C.C. Military Aviation Fuel Depot in Las Venturas, San Andreas.
Known military personnel
- Jerry Martinez (Sergeant)
- Ray Machowski (Unknown Rank)
- Victor Vance (Corporal)
- Michael Klebitz (Captain)
- Clay Simons (Unknown Rank)
- Jim Fitzgerald (Unknown Rank)
- Niko Bellic (Foreign Military, Unknown Rank)
- Darko Brevic (Foreign Military, Unknown Rank)
- Florian Cravic (Foreign Military, Unknown Rank)
- Mr Lopez (Unknown Rank)
- Barracks OL
- Jetpack (prototype experiment, stolen by Carl Johnson in 1992)
- Mesa Grande