The president of the Soviet Union (Russian: Президент Советского Союза, romanized: Prezident Sovetskogo Soyuza), officially the president of the Union of Soviet Socialist Republics (Президент Союза Советских Социалистических Республик), abbreviated as president of the USSR (Президент СССР), was the executive head of state of the Union of Soviet Socialist Republics from 15 March 1990 to 25 December 1991.

Mikhail Gorbachev was the only person to occupy this office. Gorbachev was also General Secretary of the Communist Party of the Soviet Union between March 1985 and August 1991. He derived an increasingly large share of his power from his position as president through his resignation as General Secretary following the 1991 coup d'état attempt.

The idea of the institution of a sole head of state (instead of collegial leadership) first appeared during the preparation of the draft 1936 Soviet Constitution. However, at the suggestion of the informal first person of the USSR, Joseph Stalin, who could compete with the official head of state, the idea was rejected. He formally justified the reason for this rejection as "[running] counter to the spirit of [the] Constitution", and elaborated:

According to the system of our Constitution there must not be an individual president in the U.S.S.R., elected by the whole population on a par with the Supreme Soviet, and able to put himself in opposition to the Supreme Soviet. The president in the U.S.S.R. is a collegium, it is the Presidium of the Supreme Soviet, including the President of the Presidium of the Supreme Soviet, elected, not by the whole population, but by the Supreme Soviet, and accountable to the Supreme Soviet. Historical experience shows that such a structure of the supreme bodies is the most democratic, and safeguards the country against undesirable contingencies.

Nonetheless, the establishment of a singular Presidency was considered during the elaboration of the next Soviet Constitution, both at the first attempt under Nikita Khrushchev in the early to mid-1960s and at the second, successful attempt under Leonid Brezhnev in the mid-to-late 1970s. The latter attempt at establishing a Presidency formed a part of Brezhnev's attempts at sidelining Nikolai Podgorny, who, as Chairman of the Presidium of the Supreme Soviet, was the formal head of state and first-ranked in diplomatic protocol; an alternative path to making Brezhnev head of state, by establishing a collegial State Council similar to those of East Germany, Bulgaria, and Romania, of which he would be the chairman, was also considered. In both instances, the collegial Presidium of the Supreme Soviet was ultimately retained as the highest body of power in the country.

Members of the Communist Party voted on establishing a presidency on 7 February 1990. The first and only presidential election took place on 14 March 1990. The Congress of People's Deputies decided that they would elect the first president into a five-year term, then turn over presidential elections to the public beginning in the planned 1995 presidential election.

The presidency was an executive post, based on a mixture of the US and French presidencies.

Prior to the creation of the post of president, the de jure head of state of the Soviet Union was the chairman of the Presidium of the Supreme Soviet, who was often called the "president" by non-Soviet sources. For most of the Soviet Union's existence, all effective executive political power was in the hands of the General Secretary of the Communist Party of the Soviet Union, with the chairman of the Presidium exercising largely symbolic and figurehead duties. Starting with Leonid Brezhnev in 1977, the last four general secretaries—Brezhnev, Yuri Andropov, Konstantin Chernenko, and Gorbachev—simultaneously served as de jure head of state during their time in office.