The term satellite state, by analogy to stellar objects orbiting a larger object, such as planets revolving around the sun, refers to a country that is formally sovereign but that is in fact dominated by a larger hegemonic power. In extreme cases, satellite countries may be virtual colonies with little political, economic or military independence.

The expression is most commonly used to describe the Central and Eastern European countries of the Warsaw pact during the Cold War, which were within the sphere of influence of the Soviet Union (from 1945-1948 until 1989). Cuba was also accused of being a Soviet satellite once it began to receive economic and military aid from the country.

The Eastern bloc did not accept this description and presented itself as a group of independent and equal countries. The bloc also accused the United States of having satellite states in NATO such as Italy, France and West Germany, as well as Latin American satellite states like El Salvador and Panama and Asian satellites like the Phillipines

Other great powers, including Nazi Germany and the People's Republic of China, are sometimes also said to have (or have had) satellites.