"As we welcome the third anniversary of the great Jan. 25 revolution, we call on everyone to honor it and its convoys of pure martyrs who have been and still are being killed," the now-banned movement said in a statement.
The Muslim Brotherhood's statement refers to events in 2011 that culminated with the resignation of longtime Egyptian President Hosni Mubarak. The Muslim Brotherhood supported Mohamed Morsi, who in 2012 became Egypt's first president ever elected in a democratic contest.
Morsi was removed from office by the Egyptian military in July amid growing frustration his administration was favoring the Islamic ideologies of the Muslim Brotherhood.
The movement said it made a mistake in trusting the military leadership that took power in the wake of Mubarak's resignation.
"We must restore the spirit of unity and self-denial, and pledge to continue our Revolution, in order to achieve our goals: bread, freedom, social justice and human dignity," it said.
A draft constitution meant to replace the one adopted during Morsi's tenure easily passed during a national referendum last week.