A criminal court made the ruling on Monday in the Nile Delta town of Mansoura, where the incidents took place.
Mansoura, like most Egyptian cities, witnessed a wave of violence and protests after the army's ouster of elected President Mohammad Morsi last July following demonstrations against his rule.
One judicial source said 83 Muslim Brotherhood supporters were sentenced to life in prison while 62 others were given jail sentences ranging from 3 to 10 years in jail.
Another judicial source put the total number of those sentenced to life in prison at 80, including some convicted for killing a taxi driver during a pro-Morsi protest in Mansoura in December.
Egypt has unleashed a fierce crackdown against Morsi's Muslim Brotherhood group, the state's oldest and most organized movement, killing hundreds of its supporters and jailing thousands of its leaders and sympathizers.
An Egyptian court in the southern city of Minya last Saturday confirmed a mass death sentence ruling against nearly 200 Muslim Brotherhood supporters, including the group's leader Mohammad Badie, in a case that drew harsh criticism from human rights groups.
RA/NJF