The Leopard 1A5 is the sixth variant of the Leopard 1 main battle tank family. In 1980, a research program was launched to explore further enhancements to the design, including a fully modern firing control system and a fully functional night/bad-weather vision system. It was decided that the upgrades would be based on prior variants that were no longer effective. The Leopard 1A5 variant that resulted was based on 1,225 units of the Leopard 1A1A1 subvariant. The turrets were redesigned again for the Leopard 1A5 variant, both to accommodate all of the new equipment and to relocate more ammunition to the rear of the turret, rather than placing all the ammunition to the left side of the driver, where it had previously been located. The redesigned turret could install the newer 120 mm Rheinmetall L/44 tank gun from the Leopard 2 if desired, however, this option was never utilised. Following trials, the Krupp-Atlas Elektronik EMES 18 fire control system, which evolved from the EMES 15 used on the Leopard 2 main battle tank family, was selected in December 1983. The EMES 18 has two new sights on the top of the turret that did not require the "bumps" those previous optical systems had. The Leopard 1A5 variant could be equipped with bolt-on polycarbonate (Lexan) armour plates, which improved the armour's effectiveness.

Introduced in Update "New Power", the Leopard 1A5 is the Leopard 1 main battle tank family's final production variant. It is the ultimate variant of the Leopard 1 main battle tank family, and it incorporates some of the most advanced cutting-edge technologies, many of which are from the new Leopard 2 main battle tank family. With a laser rangefinder and thermal imaging equipment, it improves the Leopard 1A5's lethality, allowing players to see adversaries first and deliver precise shots. Despite the initial plan to upgrade to the 120 mm Rheinmetall L/44 tank gun, this was not carried out since the Leopard 2s is already in production and offers many more advantages. Nonetheless, the Leopard 1A5 remained the standard armoured force of many countries across the world, and it received various minor upgrades to keep it up to date with modern battlefield requirements.