The Moscow City Court has sentenced Ukrainian Valentyn Vyhovskiy to 11 years in prison for espionage.
Russia's Federal Security Service (FSB) said on December 15 that Vyhovskiy was found guilty of collecting classified information related to Russia's aerospace technologies.
The trial was held behind closed doors.
Vyhovskiy, a 32-year-old Ukrainian businessman, was arrested last year in his native Crimea after it was annexed by Russia in March 2014.
Three other Ukrainian citizens from Crimea, including prominent film director Oleh Sentsov, were arrested on the annexed peninsula last year and sentenced later to lengthy prison terms on terrorism charges.
Sentsov, 39, denied all charges against him at his trial in August, saying that a "trial by occupiers cannot, by definition, be fair."