The Irishman, who raced in F1 from 1993 to 2002, was found guilty of injuring the son of a former Milan mayor in the Hollywood club in Milan in 2008.
Gabriele Moratti, the other man involved in the brawl, was also sentenced as both him and Irvine had accused each other of using a glass during their fight.
The sentences, however, are likely to be suspended and neither are expected to go to jail.
Irvine won four grands prix during his F1 career, finishing second to McLaren's Mika Hakkinen in the 1999 season, when the now 48-year-old was racing for Ferrari. Autosport