Leonid Romanovich Kvasnikov (2 June 1905 – 15 October 1993) was a KGB official. He graduated with honors from the Moscow Institute of Chemical Machine-Building in 1934 and worked as an engineer in a chemical plant for several years in the Gorsky region. He continued postgraduate engineering studies and joined the KGB in 1938 as a specialist in scientific-technical intelligence. Beginning in 1939 he was the section head of scientific and technical intelligence. Kvasnikov served a few short-term assignments in Germany and Poland and rising swiftly to become deputy chief and then chief of the KGB scientific intelligence section. Kvasnikov was known for his high professional level, and for his fundamental understanding of the problems of scientific and technical intelligence.
In 1940, Kvasnikov was one of the first Soviet agents to begin to investigate ongoing efforts to develop an atomic bomb. He had noticed that British, American, and German scientists who had regularly published their findings on uranium and related atomic research had ceased to publish. Kvasnikov supervised the initial KGB penetration of the British and American atomic bomb projects and in 1943 went to New York under diplomatic cover as the deputy of the Rezident. Under his management, the Soviets obtained the most important materials regarding atomic energy and its use for military purposes, and also the information and equipment models on questions of aviation, chemistry, medicine.
On his return to Moscow in 1945 Kvasnikov became deputy division head of scientific and technical intelligence, and in 1947 it headed the division until his resignation in 1963. Attained the rank of colonel and was awarded the Order of Lenin, twice the Order of the Red Banner of Labor, twice the Order of the Red Star, and other medals the Soviet Union.
- Russian Foreign Intelligence Service
- John Earl Haynes and Harvey Klehr, Venona: Decoding Soviet Espionage in America, Yale University Press (1999).