Italy is holding its general election in March and Berlusconi has announced he plans to run for prime minister again on the People of Freedom party ticket.
His defense lawyers had petitioned the court that Berlusconi's trial over allegations he had sex with an underage prostitute be postponed while he campaign for office.
The court on Friday rejected the request, Italy's ANSA news agency reported.
"We in the PdL consider the Milan Court of Appeal's decision scandalous," said PdL Secretary Angelino Alfano.
"They want to impede the head of the center-right coalition from conducting the election campaign because the hearings schedule is such that it paralyzes both Berlusconi and his lawyers who are candidates," Alfano said. "The magistrates are committing dirty tackles with their procedural decisions."