Produced in limited numbers, the Pe-8 was used to bomb Berlin in August 1941. It was also used for so-called "morale raids" designed to raise the spirit of the Soviet people by exposing Axis vulnerabilities. Its primary mission, however, was to attack German airfields, rail yards and other rear-area facilities at night, although one was used to fly the People's Commissar of Foreign Affairs (Foreign Minister) Vyacheslav Molotov from Moscow to the United States in 1942.
The prototype was built in response to a 1934 requirement, and was powered by four M-105 engines, each producing 1,100 hp and supercharged by a large blower driven by a single M-100 engine in the rear fuselage. Another prototype was fitted with AM-34FRN engines, but production aircraft were powered by AM-35As, with the ACN-2 supercharging system being deleted from the design.
Originally designated the TB-7, the aircraft was renamed the Pe-8 in 1940, to conform to the new Soviet designation system. After its primary designer, Vladimir Petlyakov, died in a plane crash in 1942, development was managed by I F Nyezeval. The type's first major mission was a raid on Berlin in mid 1941. Aircraft from the second production run were powered by Charomski M-30B diesel engines producing 1,475 hp, while third production aircraft had Shvetsov ASh-82FNV-34 radial engines, each producing 1,630 hp. Supply problems complicated the aircraft's production and the Pe-8s also had engine problems. As Soviet morale boosters, they were also high-value targets for the Luftwaffe's fighter pilots. The loss rate of these aircraft, whether from mechanical failure, friendly fire, or combat, doubled between 1942 and 1944.
By the end of the war, most of the surviving aircraft had been withdrawn from combat units. After the war, some were modified as transports for important officials, and a few others were used in various Soviet testing programs. Some supported the Soviet Arctic operations until the late 1950s.