Berezovsky, a former Kremlin insider who fell out with President Vladimir Putin and fled to Britain to avoid what he says are politically motivated charges, called the trial a "farce" in remarks broadcast on Ekho Moskvy radio.
A district court found Berezovsky guilty of using fraud to embezzle money from Aeroflot, RIA-Novosti and ITAR-Tass reported. He was charged with embezzling 214 million rubles - nearly US$9 million ( EUR 6 million) at today's exchange rates - and with laundering some of the money.
Berezovsky faces at least six years in prison on the embezzlement conviction. But Britain has rejected Russian requests for his extradition.
Berezovsky's confrontation with the Kremlin has deepened over the radiation poisoning death in London last year of Alexander Litvinenko, an ally and fellow Putin critic who blamed the Russian president for his poisoning.
Russian officials have suggested that Berezovsky, seeking to discredit Putin and Russia in the eyes of the world, was behind Litvinenko's killing and the October 2006 slaying of investigative journalist Anna Politkovskaya. Russia has refused to extradite the suspect Britain has named in Litvinenko's killing, Andrei Lugovoi.
A court-appointed attorney defended Berezovsky, who told his lawyers to steer clear of the trial.
Berezovsky was one of the richest and most prominent of the Russian tycoons who made fortunes in the political and economic upheaval following the Soviet collapse. He became an influential Kremlin insider under President Boris Yeltsin, but fell out of favor with Putin. He fled to Britain in 2000 and was granted refugee status in 2003.