The men, who were the subject of a high-profile judicial bungle this week after their arrest in Turkey, were being charged with "criminal association with the aim of planning terrorist acts", said lawyer Pierre Dunac told AFP.
The trio include the 29-year-old brother-in-law of Toulouse jihadist Mohamed Merah, who was shot dead by police after he murdered seven people, including a rabbi and three Jewish children, in a 2012 killing spree.
Another is Imad Jjebali, Merah's childhood friend, who was already convicted in 2009 for ties to a jihadi network in Iraq.
"They realised over there that it wasn't what they thought it would be, and they fled in order to go home," said Dunac, who is representing Jjebali, adding that his client "does not present a danger to France."
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The men were initially arrested in Turkey, reportedly on suspicion of being part of a network that recruited jihadists for Syria.
But in a series of glaring mishaps, they were allowed to walk free after arriving in France.
First, French authorities announced Tuesday they had arrested the men upon their arrival at Paris's Orly airport. Then it turned out the men had not flown to Paris at all.
In a further bungle, passport control failed to flag the men as suspicious, as a security databank was out of order at the time.
They handed themselves over to police on Wednesday, and were flown to Paris where they appeared before an anti-terrorist judge.
A different judge was to decide later today whether the men will be held or released pending the investigation.
French authorities are wary about nationals who have travelled to Syria and Iraq -- where the radical Islamic State controls large areas -- and may return to their home country to stage attacks.