Allegri has been under increasing pressure this season following a poor start to the campaign.
However, the 45-year-old believes that Berlusconi's visit will be a timely boost to morale inside the dressing room ahead of tomorrow's clash with Napoli.
"The visit of the president is very important and it will help to stimulate us," Football Italia quotes Allegri as saying.
"He understands that this is a difficult time and he urged us to do better. I spoke with him after the Fiorentina loss, he wanted to understand the situation."
Milan can go eighth with a win.