The Kh-55 is a Soviet/Russian subsonic air-launched cruise missile, designed by MKB Raduga in the 1970s. It has a range of up to 2,500 km (1,350 nmi) and can carry nuclear warheads. Kh-55 is launched exclusively from bomber aircraft and has spawned a number of conventionally armed variants mainly for tactical use, such as the Kh-65SE and Kh-SD, but only the Kh-101 and Kh-555 appear to have been put into service. The Kh-55 was not the basis of the submarine and ground-launched S-10 Granat or RK-55 Relief designed by NPO Novator. The RK-55 is very similar to the air-launched Kh-55 but the Kh-55 has a drop-down turbofan engine and was designed by MKB Raduga.

MKB Raduga is a Russian aerospace company, concerned with the production of various missile-systems and related technologies. It is headquartered in Dubna, Moscow Oblast. Formerly a division of the Mikoyan-Gurevich design bureau, it was spun off as a separate OKB in March 1957.