In the southern city of Huambo, the scene of some of the fiercest fighting when war resumed after the last elections - in 1992 - voting appeared to have gone smoothly.
Correspondents say people queued early to cast their ballot, and by mid-afternoon polling stations were empty save for polling officials.
Among those to vote in the capital early on Friday was President Jose Eduardo dos Santos, who said after casting his ballot that the election marked a new period in Angolan politics.
"I think we have begun a new way of conducting politics and achieving certain aims in which competition, on the basis of respect and freedom, will be the focal point."
But the head of the EU observer mission, Luisa Morgantini, said voting in parts of Luanda had been disorganised.
"The way in which on the ground things work in Luanda or at least in parts of Luanda is quite problematic," she told the BBC's Network Africa programme.
Some eight million voters are registered in the country - more than a quarter of whom live in the capital's very overcrowded conditions.
Advertisement
Angolans queue to cast their votes
The MPLA, which is the dominant political force in the country, is widely expected to win the election and consolidate its hold on power.
The party is using the poll as a dress rehearsal for next year's planned presidential election, the BBC's Peter Biles in Luanda says.
The president has already been in power for nearly 30 years - longer than Zimbabwe's leader Robert Mugabe.
Luis Samakundi, a child soldier in the war told the BBC the election was very important to him.
"For the very first time the political parties are not inciting people, especially young people, to fight against each other," he said.
"Let's hope that the result will be accepted and peace will prevail."
Angolan voters give their views on the landmark elections
Our correspondent says there is enormous hope that Angola can be set on a new path, and that democracy and stability can be reinforced.
"We believe that Angola is going to begin a new era in the east of the country after so many years of war," said Alcides Sakala, a leading Unita representative.
But he also said Unita was hoping to for more social justice. Angola is now competing with Nigeria to be Africa's biggest oil producer.
"The way wealth is distributed in our country is unjust," Mr Sakala told the BBC.
"Angola is a very rich country but today we have in this country a small group of people getting rich and a large majority without anything. If you go to the countryside you will see that."
Tension
In the lead up to the election, Unita accused the MPLA of intimidating its supporters and dominating state media.
Thursday was the first day in a week that the state newspaper Jornal de Angola carried no front-page picture of Mr Santos.
But Caetano de Sousa, head of Angola's electoral commission, said there had been a level playing field.
These elections are an important move to consolidate democracy in sub-Saharan Africa, after the troubles in Kenya and Zimbabwe this year, our correspondent says.
After independence in 1975 a power struggle ensued between the MPLA (Popular Movement for the Liberation of Angola) and Unita (Union for the Total Independence of Angola) - and up to 300,000 people died in the civil war.
Rafael Marques, a civil rights activist and journalist who covered the 1992 vote told the BBC there was no danger of a return to war, but tension remained.
"There is still some fear among the population, and to give you a very concrete example even the foreign companies operating in Angola advise their staff not to leave home, some shops have shut down days before [the election]," he said.
Will you be voting? What issues are influencing your vote? If you would be willing to speak to the BBC about your views and experiences, please include your number. It will not be published.
The BBC may edit your comments and not all emails will be published. Your comments may be published on any BBC media worldwide.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.
Bookmark with:
What are these?