The Central Election Commission said that with more than 85% of votes counted on Monday, the ruling Yeni Azerbaijan Party had won 62 seats in the 125-seat parliament, while the main Azadlyq opposition bloc had five seats.
The bloc has accused the ruling party of widespread fraud and said it will stage peaceful rallies to protest against the result.
Some feared clashes with police who have said they will not allow any disorder.
The Azadlyq bloc's leaders failed to win their own constituency races.
Independents and minor parties - many of them loyal to the government - took the rest of the seats, according to the official figures.
Ex-Soviet Azerbaijan is an emerging oil producer in a South Caucasus region crisscrossed with smouldering separatist conflicts.
Oil-hungry Western governments say they are anxious to see stable, democratic rule.
The opposition bloc is poised to
protest alleged election fraud
A repeat of the revolutions that followed disputed votes in fellow ex-Soviet republics Georgia and Ukraine was unlikely because Azerbaijan's opposition does not have the same wide popular support, analysts said.
A 600-strong Organisation for Security and Cooperation in Europe observer mission monitoring for election fraud was to give an assessment on the vote at 4pm (1200 GMT).
The ruling party claimed victory soon after polling stations closed on Sunday, saying it had regained its majority in the Milli Majlis parliament.
Yeni Azerbaijan's haul of 62 seats was down by about a dozen on the last election, but analysts said the balance of power in parliament would change little because most of the gains had been made by smaller pro-government parties.
Aliyev, who succeeded his father as head of state two years ago, runs a country of eight million Muslims wedged between Russia and Iran.
Ali Kerimli says his workers had
Corruption is endemic, and the country has yet to hold an election judged free and fair by the West.
Mazahir Panahov, chairman of the Central Election Commission, dismissed talk of fraud. "There was nothing during the election that was especially alarming," he said.
Western officials say Aliyev is trying to gradually reform his administration and the election had shown signs it might be an improvement on previous votes.
But diplomats said Aliyev was still struggling to stamp his authority on an old guard in his ruling elite that does not want to loosen its grip on power and may try to use strong-arm tactics against opposition protesters.
Ali Kerimli, an Azadlyq bloc leader who failed to regain his seat in parliament, said his workers had seen ballot-rigging, police intimidation and arrests of opposition supporters.
"We will start a peaceful struggle to have the results of these rigged elections overturned," he said.