French lawmakers voted 64 in favour and 12 against, to give France some of the most restrictive legislation on prostitution in Europe, which is a radical switch away from the nation's traditionally tolerant attitude.
Those seeking to buy sex will now face a fine of 1500 Euros, while the act of soliciting itself will no longer be punished.
Proponents of the reform point to rising human trafficking as a reason for tightening rules.
Some 90 per cent of France's estimated 20,000 to 40,000 sex workers are victims of Nigerian, Chinese and Romanian trafficking networks, the government said.
"We have decided to reinforce as much as we can the fight against human beings trafficking networks and against procurement and we have just decided to put prostitution customers in front of their responsibilities because without clients there is no prostitution, without clients there is no human trafficking," MP and member of conservative party Les Republicains, Guy Geoffroy, said.
Some feminist groups who have been pushing for an abolition of prostitution, said the law would help exploited women.
"Prostitutes will no longer be seen as criminals," Claire Quidet, a member of an anti-prostitution group, said.
"When they are abused, they can file a complaint in a police station which they did not dare doing before.
"The power relationship with their clients will be completely different as they will be in a position of strength such as 'I am not guilty, but you, what you're doing is against the law'."
Among those critical of the law was Ornela, a sex worker who said that the law will rob her of her livelihood.
"Tomorrow we will be in total insecurity," she said.
"We won't be able to declare anymore what we earn, we won't be able to pay our social taxes nor our bills.
"That's the reason why we are angry: in a way the customer will be frustrated not to be able to come to us and we will be frustrated of not being able to work and send money to the state."
The subject which divides opinion was described by one campaigner, Elisabeth Lansey, outside the National Assembly as a measure which will force prostitutes to hide away.
"If customers are penalised, they will be scared, the girls will have to hide in order to practice their trade, which is legal, and as the one who might get into legal trouble, the customer will be able to even more impose his choices, including unprotected," Ms Lansey said.
Backed by the Socialist government, the legislation has languished in parliament for nearly two-and-a-half years before being adopted on Wednesday.
