At least 27 pro-democracy groups have called for the rally to press for democratic change, with marches to set off from mosques after the noon Muslim prayer towards Tahrir, the National Front for Justice and Democracy said.
On Wednesday, Egyptians poured into the main squares of cities across the country, vowing to re-ignite their unfinished revolution, in a day billed as a celebration by the Supreme Council of the Armed Forces that took power when Mubarak was ousted on February 11.
On January 25 last year, nationwide rallies kicked off the uprising that would change the course of the Arab world's most populous nation, inspiring hopes of democratic change.
But a year later, many are disenchanted and even angry at the ruling military, who protesters accuse of reneging on promises of reform and of rights abuses.
Egypt's press on Thursday hailed the "revival" of the revolution after massive crowds took to the streets in Cairo, the Mediterranean city of Alexandria, the canal city of Suez and in the Nile Delta and Sinai peninsula.