Hundreds of demonstrators took over streets in the southern Beirut suburb Hay al-Sallum but there was no shooting or stone-throwing.
On Thursday soldiers had fired on the protesters, killing five and wounding more than 30 people in Lebanon's worst civil unrest in more than a decade. A fireman was also killed.
The Lebanese army staged a show of force on Friday. Troops and armored vehicles took up positions in the impoverished suburb - scene of the fiercest clashes - and elite soldiers guarded the nearby highway to the airport.
Syria, the main powerbroker in Lebanon, apparently intervened with various groups on Thursday night to ensure there would be no further clashes.
Thousands of people had taken to the streets after a union call for a strike to demand that the government reduce the price of 20 litres of petrol from 25,000 Lebanese pounds ($16.60) to 15,000 Lebanese pounds ($10 US).
On Friday President Emile Lahud acknowledged the economic conditions were difficult but said that rioting was unacceptable and "increases the present difficulties."
Prime Minister Rafik al-Hariri issued a statement saying he regretted the riots but warned that "chaos does not serve anyone".
Al-Hariri cut short a trip to neighboring Syria because of the violence.
Protests also took place in the southern cities of Tyre, Nabatieh and eastern city of Baalbek but there were no reports of violence.
Both sides were eager to avoid
Enraged by the killings of civilians, protesters later on Thursday stormed the Labour Ministry and set it on fire, causing extensive damage but no casualties, said witnesses.
Among the wounded were 20 Lebanese soldiers, the military command said.
It claimed that troops were forced to shoot after protesters attempted to seize military vehicles and, in one instance, hurled a hand grenade at soldiers.
Dozens of demonstrators were rounded up, said security officials. Soldiers were seen beating protesters to the ground.
High fuel prices
The violence followed a strike call by the General Confederation of Labour and Trade Unions protesting against the government's economic policies and demanding a reduction in petrol prices, from which the government collects a 40% tax.
The labour ministry was set afire
after soldiers killed civilians
Sporadic demonstrations, mostly by taxi and van drivers, blocked some roads, including the Beirut International Airport highway and the main road out of the capital toward Syria, by burning tyres.
Schools, universities and many businesses closed. Beirut's usually congested streets were almost empty as taxis and vans came to a standstill. Many travellers arriving at the airport, whose staff joined the strike for three hours, were left stranded for most of the day.
The violence died down after army troops deployed reinforcements in the tense areas.
The clashes came amid increasing anger over what is seen as the government's mismanagement of economic policies since the end of the 1975-90 civil war, causing a sharp rise in the cost of living.
The economy is shackled with US$32 billion debt, or more than 180% of the country's gross domestic product, blamed on businessman al-Hariri's borrowing to rebuild the once war-torn country.
The billionaire's Solidiere reconstruction project in the capital's downtown is also blamed for much of the debt accumulated in the last decade.
Riots in 1992 forced then-Prime Minister Omar Karami to resign, ushering in al-Hariri.
Lahud ordered an inquiry into the violence. A statement issued by the London-based human rights group Amnesty International demanded an investigation and that those responsible for human rights violations - whether protesters or soldiers - be brought to justice.
The violence came before next week's OPEC meeting in Beirut, which aims to discuss the possibility of increasing output to contain a recent rise in oil prices.