Ezz, the secretary general of Mubarak's now dissolved National Democratic Party, paid about USD 14 million as bail.
Ezz, the former owner of Ezz Steel -- Egypt's largest steel manufacturer -- was jailed within days after a popular uprising ousted Mubarak in February 2011.
He was initially charged with embezzling more than six billion Egyptian pounds.
Ezz is being retried in several cases after the cassation court overturned his sentences.
He release comes as the key members of Mubarak's regime are undergoing a rehabilitation in public opinion after the overthrow of Mubarak's Islamist successors by the army.
Mubarak himself is still on retrial for alleged involvement in the deaths of some of the roughly 800 people killed during the 18-day uprising that ended his rule.
He was sentenced in May to three years in jail on separate corruption charges.