RIA Novosti reported the Russia's General Prosecutor's office filed a criminal case in a Moscow court Tuesday against Tun Shenjun.
He was arrested Oct. 28, 2010, but the arrest was just made public, the news agency said.
Russia's Federal Security Service said Wednesday he was trying to gain access to secret information about the S-300 air-defense system.
The FSB said he was working for the State Security Ministry, China's security agency, as a translator for official delegations and was "gathering secret information from Russian citizens about technical and repair documentation for the S-300 missile system."
Russia has supplied the S-300 system to China and Beijing also is licensed to manufacture it, RIA Novosti said.
The S-300 system has been replaced by the S-400 in Russia.
Chinese authorities had not commented, RIA Novosti said.