Mahmoud El-Hefnawi, who works in the office's technical department, broke down Mubarak's wealth as $400 million in cash, $700 million in stocks and $140 million in real estate, Ahram Online reported.
Mubarak is in prison awaiting two trials on corruption charges, as well as a retrial on the killing of peaceful protesters during the 18-day 2011 uprising that led to his ouster.
He was convicted and sentenced to life in prison in June 2012 for failing to protect protesters, but successfully appealed the conviction and sentence.
Egypt's Illicit Gains Authority estimated Mubarak's fortune in 2011 at $145 million and the worth of his wife, Suzanne Mubarak, at $2.8 million, plus a villa in Heliopolis.
Mubarak's lawyer said his client's fortune totaled about $1 million.