The Lee-Metford rifle was a breech-loading British army service rifle, combining James Paris Lee's rear-locking bolt system and ten-round magazine with a seven groove rifled barrel designed by William Ellis Metford. It replaced the Martini-Henry rifle in 1888, following nine years of development and trials, but remained in service for only a short time until replaced by the similar Lee-Enfield.

Lee's bolt action mechanism was a great improvement over other designs of the day. The rear-mounted lugs placed the operating handle much closer to the rifleman, over the trigger. This made it much quicker to operate than "traditional" designs like the Mauser, which forced the rifleman to move his hand forward to operate the bolt; also, the bolt's distance of travel was identical with the length of the cartridge, and its rotation was only 60 degrees compared to the conventional 90 degree rotation of Mauser-style actions.

The Lee-Metford was introduced during a period in which most armed forces were introducing new rifles firing nitrocellulose-based smokeless propellants and box magazines with (typically) five rimless rounds. The Lee-Metford was something of an anachronism, firing a blackpowder-propelled rimmed .303 round.

The Lee-Metford started to be phased out in 1895 with the introduction of smokless cordite propellant in the cartridges. It was found that this caused excessive wear of the rifling and throat. The designs of these were modified to produce the Lee-Enfield rifle, which also incorporated modifications to the sights to compensate for the different ballistics of the new ammunition.

Replacement of the Lee-Metford rifles took several years to achieve, and they were still in service in some units at the end of the Second Boer War in 1902. British Lee-Metford and first-generation Lee-Enfield armed troops suffered stiffly at the hands of Mauser-equipped troops during the war. The longer range offered by the higher speed bullets demanded the introduction of higher-powered Lee-Enfield as soon as possible.