The Carro Armato M13/40 was an Italian World War II tank designed to replace the M11/39 in the Italian Army at the start of World War II. It was the primary tank used by the Italians throughout the war. The design was influenced by the British Vickers 6-Ton and was based on the modified chassis of the earlier M11/39. Production of the M11/39 was cut short in order to get the M13/40 into production. The name refers to "M" for Medio (medium) according to the Italian tank weight standards at the time, 13 tonnes was the scheduled weight and 1940 the initial year of production.
The M13/40 was used in the Greek campaign in 1940 and 1941 and in the North African Campaign. The M13/40 was not used on the Eastern Front; Italian forces there were equipped only with L6/40s and Semovente 47/32s. Beginning in 1942, the Italian Army recognized the firepower weakness of the M13/40 series and employed the Semovente 75/18 self-propelled gun alongside the tanks in their armoured units.
The M13/40 series was Italy's most-produced tank of the war with over 3,000 having been built, including later variants such as the M14/41.