The T-64 is a Soviet tank manufactured in Kharkiv, and designed by Alexander Morozov. The tank was introduced in the early 1960s. It was a more advanced counterpart to the T-62: the T-64 served in tank divisions, while the T-62 supported infantry in motorized rifle divisions. It introduced a number of advanced features including composite armour, a compact engine and transmission, and a smoothbore 125-mm gun equipped with an autoloader to allow the crew to be reduced to three so the tank could be smaller and lighter. In spite of being armed and armoured like a heavy tank, the T-64 weighed only 38 tonnes (42 short tons; 37 long tons).

These features made the T-64 expensive to build, significantly more so than previous generations of Soviet tanks. This was especially true of the powerpack, which was time-consuming to build and cost twice as much as more conventional designs. Several proposals were made to improve the T-64 with new engines, but chief designer Alexander Alexandrovich Morozov's political power in Moscow kept the design in production in spite of any concerns about price.[citation needed]

The T-64 formed the design basis of the Soviet T-80,[3] which entered service in 1976. The tank is in use in a few nations or regions as of 2023. The T-64 is undergoing significant factory overhauls and modernization in Ukraine.