Alexander Vassiliev (Russian: Александр Васильев; born 1962) is a Russian journalist, writer, and espionage historian living in London. A former officer in the Soviet Committee for State Security (KGB), Vassiliev is known for his two books based upon KGB archival documents: Spies: The Rise and Fall of the KGB in America, co-authored with John Earl Haynes and Harvey Klehr, and The Haunted Wood: Soviet Espionage in America: the Stalin Era, co-authored with Allen Weinstein.