Roman Ushakov was found guilty and sentenced yesterday for trying to transmit coded documents from the Russian interior ministry to the United States' Central Intelligence Agency, Russian news agencies reported.
Prosecutor Viktor Antipov, said the former police officer from the Siberian city of Krasnoyarsk was caught red-handed placing the documents which had been "requested" by the CIA under a fake rock.
He said investigators had found 37,000 euros (USD 40,000) in cash and a thank-you letter from the CIA under the rock.
Nine people have been arrested for high treason in the Russian capital alone since the beginning of 2014, the Moscow City Court was quoted as saying by Russian news agencies.
Observers say the cases have been trumped up by the authorities in what is seen as a fresh effort to clamp down on dissent.
"This is absolute absurdity," special services analyst Irina Borogan told AFP, adding that Ushakov had likely been set up by Russia's federal security agency FSB - the successor to the Soviet-era KGB.
Rights groups have expressed alarm over broadened definitions of treason and espionage that were put in place when Putin returned to the Kremlin for a third term in 2012.
Nearly anyone, including those without access to state secrets, could fall afoul of the vague legislation.
Mother of seven Svetlana Davydova was arrested on espionage charges in January for allegedly calling the Ukrainian embassy with information on Russian troops movements, and became a cause celebre for the country's embattled civil society.
"There have been many absurd cases since the 2000s, but now the climate of fear around spies has worsened due to the conflict in Ukraine," said Borogan.
