Ex-King Peter of Yugoslavia denounced Marshal Tito's government as a "police state worse than any Nazi regime" before an audience of 750 at the Business School yesterday.

The 25-year-old deposed ruler of the Balkan state, who has been in this country about a month, spent yesterday on the south bank of the Charles "studying American business methods' and talking to faculty members and newspapermen.

Outside the Baker Library, where he spoke, the Yugoslav tricolor flew.

At a press conference prior to his public remarks the former monarch indicated that he was more concerned for his people's freedom and welfare than his own restoration to power.

"I am not so important," he observed in answer to a question about the political future of his country. "What matters is the self-determination of the people of Yugoslavia."

He expressed the belief that less than one fifth of his countrymen supported Tito, even with his new nationalistic anti-Cominform policy. Despite the recent rift between Tito and Stalin, he hoped that the United States would not be duped into supporting the Tito regime.