Fijians are voting in the country's first general election since the post-coup vote in 2001.
Voters faced long queues in some areas
The poll pits Prime Minister Laisenia Qarase's Fijian-dominated SDL party against the predominantly ethnic Indian Labour party of Mahendra Chaudhry.
Relations between native Fijians and ethnic Indians, who make up almost 40% of the population, have been tense.
Voting began peacefully, although the start was delayed in some areas with the late arrival of ballot papers.
Police were clearly visible around polling stations, which were opened at 0700 local time on Saturday (1900 GMT on Friday).
But in some areas, the lack of ballot papers led to queues of thousands of people, some of whom were told to return later, Reuters news agency reports.
In the rural west of the main island of Viti Levu, election officials agreed to keep polling stations open an hour later because some people were kept waiting for up to three hours.
During the poll, 2,000 ballot boxes will be distributed to the 100 of Fiji's 320 islands which are inhabited.
Voting is due to last until 13 May, and the ballot-counting is expected to take four days.
Twelve parties are trying to win seats in the 71-member parliament. The SDL and the Labour party are expected to win the majority of the seats between them.
Fiji has never really recovered from a nationalist uprising six years ago, says the BBC correspondent in Sydney, Phil Mercer.
It highlighted the deep differences between the races that are still apparent. In May 2000, armed gunmen stormed the parliament compound and deposed the country's first ethnic Indian Prime Minister, Mahendra Chaudhry.
He was eventually replaced by Laisenia Qarase, a hardline indigenous leader.
Tensions between the two men are well known and reflect the suspicions that exist between native Fijians and ethnic Indians.
Army chief Voreqe Bainimarama has said the military will back whichever government is elected.
Commodore Bainimarama has been engaged in an angry dispute with Mr Qarase over a controversial amnesty bill that would allow leaders of former coups, such as George Speight who led the 2000 coup, to apply to be released.
Voters cast two ballots - one for an "open" seat and one for a representative of their own community.
Twenty-five seats in the parliament are "open", and the rest are reserved for different ethnic groups. Twenty-three are reserved for indigenous Fijians and 19 for ethnic Indians.
About 51% of Fiji's estimated 906,000 people are indigenous Fijians of Melanesian and Polynesian ancestry.
Ethnic Indians make up about 44%. Their ancestors were brought to the islands as sugar farmers in the 19th century by former colonial power Britain. Other ethnic groups make up 5%.
Foreign observers, including a group from the European Union, will monitor the election.