Berlusconi has maintained a strategic silence in recent days after several outbursts from Leonardo against the Italian PM.
Leonardo is expected to be shown the door at the end of the season and Inzaghi told La Stampa: "Berlusconi is more important.
"The important thing is that HE stays. We have won many things at Milan because of him. We owe our success to him."
On his own future, Inzaghi added: "It's up to me to decide when to stop playing, the time has not arrived yet. I still want to beat some records, I want to do that with this shirt and these fans who have given me so much love."