The Military Base is located somewhere in the outskirts of Lower Paradise, and it is where the National Guard are deployed from. On Sunday, Postal Dude is arrested by the National Guard at the Terrorist Training Camp during his escape. He is taken to the Military Base where he has to share a cell with a terrorist, of whom he sets on fire with Matches in order to start the sprinklers and open all cell doors. The Dude then shoots his way through the base, killing numerous soldiers in the process. During the escape, he comes across an ordnance silo filled with nuclear warheads and artillery shells. One stands out from the rest, being a Thermo-nuclear warhead. Thinking it will be enough to bring down the Bullfish Interactive headquarters, the Dude takes the Thermo-nuclear warhead and continues to escape the base whilst having periodic Hallucinations. The main gates of the base are broke open by zombies, who attack the soldiers and give them things to shoot at other than Postal Dude, who manages to run out through the gates and back into Lower Paradise.
- The Military Base segment of the game is split into four parts due to its length.
- The base has hangars and a number of A-10 Thunderbolts. Ironically, there is no runway long enough for them to take off. What is even more funny is that they are placed on cinderbricks
- If the Postal Dude kicks one of the warheads located at the silo, the game will be interrupted by a clip of the Earth exploding, obviously killing the Postal Dude in the process, due to the vast number of bombs in the place, and triggering a game over.