An anti-tank rifle is an anti-materiel rifle designed to penetrate the armor of armored fighting vehicles, most commonly tanks, armored personnel carriers, and infantry fighting vehicles. The term is usually used for weapons that can be carried and used by one person, but is sometimes used for larger weapons. The usefulness of rifles for this purpose ran from the introduction of tanks in World War I until the Korean War. While medium and heavy tank armor became too thick to be penetrated by rigid projectiles from rifles that could be carried by a single soldier, anti-tank rifles continued to be used against other "soft" targets, though recoilless rifles and rocket-propelled grenades such as the bazooka were also introduced for infantry close-layer defense against tanks.

An anti-materiel rifle (AMR) is a rifle designed for use against military equipment, structures, and other hardware (materiel) targets. Anti-materiel rifles are chambered in significantly larger calibers than conventional rifles and are employed to eliminate equipment such as engines and unarmored or lightly armored targets. While modern armored vehicles are resistant to anti-materiel rifles, the extended range and penetration still has many modern applications. Although not intended for use against human targets, the bullet weight and velocity of anti-materiel rifles gives them exceptional long-range capability even when compared with designated sniper rifles. Anti-materiel rifles are made in both bolt-action as well as semi-automatic designs.