The Survey Corps, also known asthe Scouting Legion, Scout Regiment, or Recon Corps, is the driving force of the plot and story as it is the branch of the Military most actively involved in direct Titan combat, Titan study, human expansion, and outside exploration. They have the best soldiers (not to be compared with the Top 10 who joins the Military Police), and are the most skilled in using the 3DMG (Three Dimensional Maneuver Gear). But despite having little success, they still symbolize 'the hope of mankind', their insignia being known as 'the Wings of Freedom'. This military division is in charge of the exploration and the eventual reclamation of human territory from Titan-infested lands through the act of setting up small bases, camps, resupply stations, and extra fortifications in available areas outside the walls. The Survey Corps is the smallest branch of the military in terms of membership, with an overall size of around 300 soldiers. This already limited number of volunteers is made less and less by commonplace deaths and an infamy surrounding the body count that frightens most away from joining.

The Military Police Brigade isthe most prestigious due to their work allowing them to live safely within the Inner Wall, abundant resources, and higher authority over other military sectors. However, in reality it is the most corrupted military sector due to a lack of oversight compared to the other sectors of the military. Due to their misuse and abuse of authority, the Military Police Brigade is also at odds with the Garrison and especially with the Survey Corps. Only the top ten alumni from trainee squads can apply for the Military Police Brigade. The Military Police Brigade is the primary police force within human territory. Not only do they maintain order, they serve as the king's guard. Since they do not normally come in contact with Titans, they must have special permission to use 3D Maneuver Gear and usually carry firearms such as rifles instead. They are also in charge of tax collection and land distribution. They usually abuse these duties to exploit resources and food from civilians.

The Garrison, also known as theStationary Guard, is the largest of the Military divisions which protects and maintains order near 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), cannonading, security detail, crowd control, and rifle usage.The Garrison takes care of all defenses for the Wall 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 Wall that are often used for long-range Titan defense. They must also deal with civilian evacuation and have emergency plans for dealing with scenarios for when the Walls are breached to make sure the citizens are evacuated safely.

Trainees Squad

The 104th Trainees Squad is theonly graduating class introduced in the series and the Southern division contains nearly all of the central characters.As with all graduating classes, only top ten in class can apply to the Military Police Brigade, giving them the privilege of living in the Inner District. There's a total of 218 graduates of the 104th Trainees Squad Southern Division.