Venezuela's National Assembly, dominated by Chavez's allies, approved the modified flag last week after he proposed changes as a tribute to Simon Bolivar, the Venezuelan-born South American liberation hero who Chavez says inspired his socialist revolution.
A small group of Chavez supporters briefly traded blows with opposition marchers protesting against the new flag, which features an eighth star, a white horse on the coat of arms galloping to the left instead of the right, a bow and arrow representing Venezuela's indigenous people and a machete to represent the labourers.
In a ceremony on the 200th anniversary of the country's flag, Chavez raised the new version at the national pantheon before attending a military parade where soldiers marched with participants in his social programmes for the poor.
Stars and gripes
"Eight stars now flutter in the wind in Venezuela, seven originals and the eighth that Simon Bolivar decreed," Chavez said. "And the white horse is now free."
The president said Bolivar decreed in 1817 that another star should be added to the flag to represent the addition of a province to Venezuela.
Chavez's presidential sash bore
the old coat of arms
Since 1863, the flag has had seven stars representing the original seven provinces that rose up against Spain.
Chavez, a former soldier, was elected seven years ago and has promised a revolution for the poor in the world's fifth-largest oil exporter.
His critics at home and in Washington worry about his alliance with Cuba and say he has eroded democracy by exercising authoritarian control.
Critics call the changes to the flag a waste of money. The new flag and coat of arms is eventually to be adopted in Venezuela's currency, passports and government documents.
Several hundred opposition supporters marched in Caracas to protest against the new flag. One group of demonstrators carried seven white stars and an eighth red one painted with the former Soviet hammer and sickle emblem.
Scuffles briefly broke out after Chavez loyalists hoisted the new flag along the route of the protest march and opposition supporters tried to take it down. Police quickly quelled the clashes.
The new flag flying over the
national cemetery in Caracas
Rosa de Pool, 70, a secretary participating in the opposition protest, said: "I'm here to defend my flag, you can't change those things without asking the people if they agree or not."
Lilian Luces, 54, said: "It's a whim of the president. I think it's absurd for them to put on another star and turn around the horse."
Last year Chavez dismissed the horse image on the flag as "imperialist" after his daughter asked him why it ran to the right with its head facing backward.
"The white horse is now liberated, free, vigorous, trotting toward the left, representing the return of Bolivar and his dream," Chavez said. "Long live the fatherland!"
However, the government apparently did not have time to update Chavez's presidential sash, which bore the old coat of arms with the horse galloping towards the right.