By an overwhelming 276-20 majority, the French Senate late on Wednesday passed the bill that the National Assembly - the lower house - had approved by 494 to 36 votes on 10 February.
The ban, which targets the hijab (headscarves) but also outlaws Jewish skullcaps and large Christian crosses, comes into effect in September.
Politicians and teachers had clamoured for it to stem a perceived wave of Islamic radicalism among Muslim youths.
"We wanted to send a swift and strong message," Prime Minister Jean-Pierre Raffarin said of the law, adding he had "neither the feeling nor the conceit to believe that this text has solved everything".
"Our plan is not aimed against any religion," he declared, defending the law against criticism it received from France's Muslims and other religious groups, Islamic countries and Pope John Paul.
Raffarin claims the new law is
not against any religion
In contrast to the heated public discussions before the National Assembly vote, the Senate debate passed off "in serenity, if not indifference", as the daily Le Figaro put it.
Education Minister Luc Ferry has announced he will meet leaders of all concerned religious groups to see if they can work out compromises within the new law.
Dalil Boubakeur, head of the French Council of the Muslim Faith (CFCM), has urged him to let schoolgirls wear a small bandanna in place of the voluminous scarves that cover their hair, ears, throats and shoulders.
France's 5,000-strong Sikh community, initially overlooked in the debate, will also negotiate with the ministry to let boys keep their traditional head coverings at school.
"This law is only a symptom, it's not the real problem"
Leaders of France's five million Muslims see the law as deeply discriminatory and feel politicians used the hijab to mobilise voters before this month's regional elections.
"This law is only a symptom, it's not the real problem," said Tariq Ramadan, a Swiss Islamic scholar with a wide following among disaffected French Muslim youths.
"France is changing and the average Frenchman is afraid. The politicians are trying to satisfy voters by telling them they won't allow multiculturalism," he said.
The real problem facing France was its failure to integrate Muslims and tackle the discrimination they face, he said.
More is to follow. Prime Minister Raffarin announced last month that the hijab ban would be followed by a law on public hospitals aimed at forcing traditional Muslims to follow western customs when seeking medical care.
In recent years, growing numbers of Muslim men have refused to be examined by a woman and have stopped male doctors from treating their wives. Some women will not undress for a checkup.