Yuri Fyodorovich Orlov (Russian: Ю́рий Фёдорович Орло́в, 13 August 1924 – 27 September 2020) was a particle accelerator physicist, human rights activist, Soviet dissident, founder of the Moscow Helsinki Group, a founding member of the Soviet Amnesty International group. He was declared a prisoner of conscience while serving nine years in prison and internal exile for monitoring the Helsinki human rights accords, he was declared a prisoner of conscience by Amnesty International as a founder of the human rights movement in the Soviet Union. Following his release from exile, Orlov was allowed to emigrate to the U.S. and became a professor of physics at Cornell University.

Yuri Orlov was born into a working-class family on 13 August 1924 and grew up in a village near Moscow. His parents were Klavdiya Petrovna Lebedeva and Fyodor Pavlovich Orlov. In March 1933, his father died.

From 1944 to 1946, Orlov served as an officer in the Soviet army. In 1952, he graduated from the Moscow State University and began his postgraduate studies at the Institute for Theoretical and Experimental Physics where he later worked as a physicist.

In 1956, Orlov nearly lost his scientist career due to his speech at the party meeting about discussion of the report "On the Personality Cult and its Consequences" by Khrushchev at the 20th Congress of the CPSU. He publicly called Stalin and Beria "killers who were in power" and put forward the requirement of "democracy on the basis of socialism." For his pro-democracy speech in 1956, he was expelled from the Communist Party of the Soviet Union and fired from his job.

What is the meaning of life? That your soul may outlive your remains in something sacred and should escape decay ... I have again looked at, added up, corrected, and sized up what I have been doing during these last years and have seen that this is good ... (Yuri Orlov, 1980)

Orlov obtained the Candidate of Sciences degree in 1958 and the Doctor of Sciences degree in 1963. He became an expert on particle acceleration. In 1968, he was elected a corresponding member of the Armenian Academy of Sciences after he found work at the Yerevan Physics Institute. In 1972, he came back to Moscow and worked at the Institute of Terrestrial Magnetism.

In September 1973, when Pravda published a statement by a group of prominent academics denouncing Andrei Sakharov's anti-patriotic activity, Orlov decided to support him, while recollecting the well memorized spells of the 1930s, in which some academics demanded the death penalty for others already arrested; later some of these academics themselves were arrested, with some academics who were not arrested demanding the death penalty for them.

Defending Sakharov, Orlov on 16 September 1973 wrote "Open Letter to L.I. Brezhnev about the Reasons for the Intellectual Backwardness in the USSR and Proposals to Overcome It" which appeared in underground samizdat circulation. The Western press published the letter in 1974 but publication in the Russian press was only in 1991. In the early 1970s, the article by Yuri Orlov "Is a Non-Totalitarian Type of Socialism Possible?" also appeared in underground samizdat circulation.