The former Italian prime minister, who is currently appealing a one-year sentence for tax fraud, was sentenced to another year in jail for leaking a police wire-tap of a political rival to his brother Paolo's newspaper in 2005.
The rival, former left-wing leader Piero Fassino, was recorded in conversation with the head of an insurance company that was in the process of buying out BNL bank.
Police were investigating possible political interference into the buyout, but Silvio Berlusconi used his position of power as prime minister to obtain the recording, with his brother then publishing it in his Il Gornale newspaper.
Paolo Berlusconi was given two years and three months in prison for breaching confidentiality, the same charge his brother faced.
Later in March Silvio Berlusconi, who returned to politics for this year's general election but failed to win a majority, is also set to receive a verdict in his infamous sex trial.
While he is unlikely to actually go to prison for either the tax fraud or wire-tap convictions, he could well find himself in bigger trouble over accusations he had sex with an underage prostitute.
The flamboyant telecommunications billionaire has fought off numerous charges over the years, including false accounting, bribery, perjury and corruption.