The lion's share - $300 million - was held by Mubarak's elder son Alaa, a businessman who kept out of politics, said Assem al- Gohari, who heads the Illicit Gains Authority.
The balance was held by his younger son Gamal, a leading former ruling party politician who had widely been seen as his father's heir apparent.
Both sons are in custody in a Cairo prison as they stand trial on an array of charges, including corruption.
The assets of Mubarak's two sons make up the great majority of the $460 million in Egyptian funds frozen by the Swiss government since the veteran strongman's overthrow in February, the official MENA news agency quoted Gohari as saying.
Switzerland vowed last Wednesday to expedite the return of funds once held by members of the Mubarak regime and that of ousted Tunisian strongman Zine El Abidine Ben Ali.
"Switzerland is the seventh financial centre in the world. It is the first in terms of restitution of funds stolen by dictators," said the foreign ministry's head of the international public law department Valentin, Zellweger, quoted by the ATS news agency.