A recording tape cartridge includes two first guide wall portions formed in a direction orthogonal to a loading direction of the case into a drive device and between which a first protruding wall portion formed at a brake member is insertable, and two second guide wall portions and two third guide wall portions formed at regular intervals from the first guide wall portions in a circumferential direction. A second protruding wall portion at the brake member is insertable between the second guide wall portions, and a third protruding wall portion at the brake member is insertable between the third guide wall portions. An interval, α, between each first guide wall portion and the first protruding wall portion, and an interval, β, between each second guide wall portion and the second protruding wall portion and between each third guide wall portion and the third protruding wall portion satisfy “α≥2×β”.