The 508-member assembly was dissolved in February 2011 by the Supreme Council of the Armed Forces that took power when Mubarak was forced to step down.
Egypt’s first democratic parliamentary elections, held in phases between November and earlier this month, saw Islamists clinch nearly three-quarters of the seats.
The long-banned Muslim Brotherhood won a crushing victory with 47.18 percent through its political arm, the Freedom and Justice Party (FJP).
The ultra-conservative Salafist Al-Nur party came second with 24.29 percent, with the liberal Wafd party finishing a distant third.
The packed first session was chaired by parliament’s most senior member, Mahmud al-Saqqa of the liberal Wafd party, ahead of a vote for parliament’s speaker.
The Brotherhood, Egypt’s best organised political grouping, had been widely expected to triumph in the polls but the surge by Al-Nur and high visibility of Salafi movements have raised fears about civil liberties and religious freedom.
Outside parliament, hundreds of Islamist supporters greeted deputies on their way in, in scenes unimaginable just a year ago when most Islamist movements were banned.
The exact role of parliament remains unclear, with power remaining in the hands of the generals who took power from Mubarak.
Elections for parliament’s upper house, the Shura Council, are to begin later this month and end in February. Then the two chambers will choose a 100-member panel to draft a new constitution.
According to AFP, the SCAF has vowed to cede power to civilian rule by June when a new president is elected.