Judge Mohammed Nagi Shehata handed down the verdict against the 230 defendants at the Cairo Criminal Court on Wednesday.
The case relates to clashes that erupted between protesters and security forces in central Cairo in December 2011, several months after autocrat Hosni Mubarak was forced to step down. Dozens were killed in the violence.
Prominent pro-democracy activist Ahmed Douma (pictured) was among those given a life sentence. He played a key role in the uprising against Mubarak, and in the protests against Islamist President Mohammed Morsi, who was ousted by the military in 2013.
Douma, who is already serving three years for violating a protest ban, was also fined 17 million Egyptian pounds (1.9 million euros or $2.2 million) for damage caused to cabinet headquarters and other state property during the violent 2011 protests.
Hundreds of Morsi's supporters have been sentenced to death as part of a government crackdown overseen by President Abdel-Fattah el-Sissi, but Wednesday's ruling is the harshest court order yet to be delivered against non-Islamist activists.
The life sentences, which amount to 25 years in Egypt, can be appealed.
Judge Shehata made international headlines last year when he sentenced three Al-Jazeera English journalists to prison after convicting them in June on charges of aiding the outlawed Muslim Brotherhood, the party of ousted president Morsi.
One of those journalists, Australian Peter Greste, was deported on Sunday under a presidential decree.
On Monday, Shehata sentenced 183 men to death for a deadly attack on a police station in Cairo in 2013.
nm/kms (AP, AFP, Reuters, dpa)