The guards of the city of Minas Tirith, and in particular those who guarded the White Tower and the Court of the Fountain in the highest tier of the city. These were the only soldiers in the city who wore the ancient livery of Elendil himself: a black surcoat with a shining white tree, with a silver crown and stars above it. There were at least three companies of these guards keeping watch over the Citadel of Gondor.

In almost all cases, these guards with their black-and-white uniforms are specifically associated with the Citadel and its White Tower (and indeed, they are usually called the Guard of the Tower or Guards of the Citadel). Only once are they described more generally 'Guards of Minas Tirith' (that is, of the whole city, rather than the Citadel at its peak). This is during Samwise Gamgee's first encounter with a guard bearing the white-tree-on-black emblem at the Field of Cormallen, and so perhaps it reflects Sam's unfamiliarity with the guards' exact role, rather than being any kind of formal term.