The Sukhoi Su-34 (Russian: Сухой Су-34; NATO reporting name: Fullback) is a Soviet-origin Russian twin-engine, twin-seat, all-weather supersonic medium-range fighter-bomber/strike aircraft. It first flew in 1990, intended for the Soviet Air Forces, and it entered service in 2014 with the Russian Air Force.

Based on the Sukhoi Su-27 Flanker air superiority fighter, the Su-34 has an armoured cockpit with side-by-side seating for its two pilots. The Su-34 was designed primarily for tactical deployment against ground and naval targets (tactical bombing/attack/interdiction roles, including against small and mobile targets) on solo and group missions in daytime and at night, under favourable and adverse weather conditions and in a hostile environment with counter-fire and electronic warfare (EW) counter-measures deployed, as well as for aerial reconnaissance. The Su-34 is planned to eventually replace the Su-24 tactical strike fighter and the Tu-22M long-distance bomber.