It had been reported that the vice president and chief executive officer would leave the club after Berlusconi's daughter Barbara suggested she would be taking over from him.
The 69-year-old had also been linked with a move to Ligue 1 champions Paris Saint-Germain to take up the role left by Leonardo at the end of last season.
However, Galliani has insisted he will remain at San Siro for the foreseeable future under the ownership of Berlusconi.
"Silvio Berlusconi will be my president for life," he said. "He is the best in the world and there is no truth in these rumours about PSG or any other club.
"If I stay in football, then it will only be at Milan. We've been working together for 34 years."
Galliani has been involved in brokering big transfers for Milan during his tenure at the club, including signing Mario Balotelli and Kaka in the past 12 months.
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