President Hosni Mubarak, who has ruled Egypt for 24 years, has been sworn in for a fifth term in office.
Hosni Mubarak won the first contested election by vast margin
He won Egypt's first contested election three weeks ago when he took 88.6% of the votes, although less than a quarter of the electorate voted.
Opposition groups dismissed the ballot as a fraud, but electoral officials have rejected calls for a re-run.
Several ambassadors and dignitaries, including Libyan leader General Muammar Gaddafi, attended the ceremony.
"I swear by almighty God to uphold the republican system with loyalty, to respect the constitution and the law, to look after the interests of the people fully and to safeguard the independence and territorial integrity of the motherland," Mr Mubarak said in parliament.
Canons were fired from the parliament compound after Mr Mubarak pronounced the presidential oath.
On Saturday, about 2,000 people took to the streets of Cairo, the capital, in a protest against Mr Mubarak's re-election.
Mr Mubarak, who previously had been elected only in single-candidate referendums, changed the system earlier this year under pressure from the US and domestic political groups.