The right to remove passports was introduced as part of a raft of new counter-terrorism laws in November aimed at curbing the number of French citizens leaving to join jihadist groups in the Middle East.
A security source said the six French were "imminently" about to travel to Syria.
Their passports and identity cards have been confiscated for six months, after which the order can be renewed.
"There will be more," said Prime Minister Manuel Valls when asked about the case on Monday.
Some 1,400 people living in France have either joined the jihadist cause in Syria and Iraq or are planning to do so, Valls said last month.
France's Interior Minister Bernard Cazeneuve said another 40 individuals will also have their passports confiscated in the coming weeks.
"There are currently six administrative bans on leaving the country that have already been signed, and around 40 that are being prepared," Cazeneuve told reporters.
The concern in France about what to do about jihadists leaving and returning to the country has been heightened since the January terror attacks.
According to polls the French public want more repression and would rather see jihadists locked up rather than integrated into society.
The public would presumably be happy with the kind of sentence that saw a jihadist jailed for seven years after only spending 12 days in Syria.
Out on the streets of Paris, many people The Local spoke to also want to see courts get tough on extremists.
“We have to make them suffer,” Rachid, a café manager said.
"Today prisons are like a holiday camp. Inmates should not be able to have any kind of contact with the outside world,” he added.
Pierre Gauthier, aged 51 said: “We have to extend their sentences and establish prison terms without minimum sentences.”
The country’s Justice Minister Christiane Taubira told The Local and other foreign reporters recently that French culture demands that “those who cross the line are punished. Full stop.”