Arcadi Gaydamak (also spelled Arkady Gaidamak, Russian: ????) (born ???? in Moscow, Russia) is a Russian businessman and financier, and member of the wealthy Gaydamak family. His son Alexandre Gaydamak is also a successful businessman.

He spent his early childhood in Moscow, before moving to Israel at a young age and later moved to France, where he entered business in the late 1980s.

Gaydamak spent many years in France, but fled the country when an arrest warrant was issued for him. He is wanted on two charges; illegal arms dealing with Angola, and tax evasion. Gaydamak, whose wealth is estimated at anywhere from $800 million to more than $1 billion, has lived permanently in Moscow since 2002.

As well as his main businesses, Gaydamak is the owner of Israeli association football (soccer) club Beitar Jerusalem FC. He is also the patron of several Jewish charities, and is president of the Congress of Jewish Religious Communities and Organizations of Russia, (KEROOR), Russia's oldest religious Jewish umbrella group.