Mubarak, 86, is accused along with seven of his former police commanders of involvement in the killing of hundreds of demonstrators during the 2011 revolt that ended his three-decade rule.
An appeals court overturned an initial life sentence for Mubarak in 2012 on a technicality.
The new verdict was initially scheduled for September 27, but chief judge Mahmud Kamel al-Rashidi postponed it, saying he had not finished writing the reasoning after a retrial that saw thousands of case files presented.
If acquitted, he would not be released because he is serving a three-year sentence in a separate corruption case, a judicial official said.
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Today's verdict comes as the revolutionary fervour that unseated Mubarak has largely ebbed across the country.
Mubarak's Islamist successor Mohamed Morsi was himself removed last year by then-army chief Abdel Fattah al-Sisi, who is now president, and put on trial along with hundreds of other Islamists.
Morsi and several top leaders of his Muslim Brotherhood movement are accused of committing acts of violence during the anti-Mubarak uprising as well as during huge anti-Morsi protests which prompted the army to remove him.
Sisi, who won a presidential election in May after crushing his Islamist opponents, has made law and order and economic stability his top priorities rather than democratic freedoms - the key demand during the anti-Mubarak uprising.
The police force, which Mubarak is accused of ordering to quell the 2011 uprising, is now feted in the largely pro-government media as it wages a deadly crackdown on pro-Morsi Islamist protesters and militants.