The Garrison (駐屯兵団 Chūton Heidan) is the largest of the Military divisions which protects and maintains order within the Walls. Given the fatality rate of the Survey Corps and the limited entry of the Military Police Brigade, most soldiers join the Garrison. As they often have close contact with both Titans and human civilians, they are proficient over a wide variety of tasks such as Titan combat (defensive battles), cannons, security detail, crowd control, and rifle usage.

Duty:
The Garrison takes care of all defenses for the Walls whether it be patrols, repairs, or improvements. As such, they spend most of their time preparing for attacks against the Wall. The Garrison mans the cannons on the Walls that are often used for long-range Titan defense. They must also deal with civilian evacuations and have emergency plans for dealing with scenarios for when the Walls are breached to make sure the citizens are evacuated safely.

Structure:
The Garrison is the largest of the three branches, with a total of 30,000 soldiers. Members of the Trainee Corps are considered in this total until their graduation and enlistment in a chosen branch. Their total number of combat-ready personnel is a mere 3rd of this total, at 10,000 soldiers. Their structure consists of Regiments, Brigades, and Divisions. A regiment is the smallest unit, consisting of 1,000 soldiers. A Brigade consists of anywhere between 2,000 and 3,000 soldiers, or 2-3 regiments. And finally, the largest units are Divisions, which consist of 2 Brigades.

Qualities:
Being the main fighting force of the vertical equipment soldiers, the men and women of the Garrison come from all backgrounds and views. There are those who joined and are simply afraid of dying or unwilling to give their lives for what they believe to be foolish causes, although many are fiercely devoted to the protection of mankind, having joined the Garrison simply to protect loved ones from the threat of Titans. Members of the Garrison usually work by themselves but will join with the Survey Corps when needed.