Mubarak (84) along with former interior minister Habib al-Adly and six others could face the gallows if convicted of ordering the deaths of some of the estimated 850 people.
The case also includes the president's sons Alaa and Gamal.
They are accused of killing peaceful protesters and wasting public funds.
The Interior Ministry has taken special measures to secure the premises of the court, where the trial is taking place.
The wall around the police academy in New Cairo, a satellite city around the capital, has already been raised to four metres in addition to another metre of barbed wire.
The court also refused to issue any new permits to cover the trial and kept the coverage exclusive for state-owned TV. The trial would be broadcast live to the world.
Mubarak will be flown to the court from a hospital, where he has been held since his arrest last year.
Legal experts have predicted different sentences for the ousted president, but they all agree the death penalty is not an option.
If Mubarak receives a strict sentence, the next president or the ruling Supreme Council of the Armed Forces might grant him amnesty.
Around a hundred lawyers are calling for retribution for those killed in the January revolution, while 22 lawyers are defending the accused.