Maelys de Araujo was last seen in the early hours of Sunday August 27 at a community hall where the wedding was held in Pont-de-Beauvoisin, a village some 50 kilometres (30 miles) north of Grenoble.
A 34-year-old man has been charged with "kidnapping, illegal confinement or arbitrary detention of a minor of less than 15 years" following the police probe, Grenoble's prosecutor said in a press release issued late Sunday.
The man was at the wedding during which the little girl -- who was attending the event with her parents -- went missing, the statement said.
Maelys, who has dark brown hair and eyes, has not been seen since.
Scores of police, search and rescue teams, divers and cavers have spent the week trawling through the heavily wooded area near where the wedding was held for signs of her.
The charged man is one of two suspects who were detained Thursday over inconsistencies in their statements, but then released Friday evening.
"Brought before investigating judges at the end of the afternoon, he contested the facts. Confronted with testimony, findings and scientific evidence, he persisted in his denials and explanations," the statement said.
"This did not convince the investigative judges, who decided to hold him," it added.
"After the debate... between the prosecutor and the defence," the man was placed "in provisional detention," the statement added.
The prosecutor indicated that fresh evidence uncovered during the police probe had led to the suspect, who had been released, being recalled and questioned again.
According to a source close to the investigation, police technical and forensic teams had found DNA evidence and were trying to determine whether the missing girl had been in the suspect's vehicle.
The car had previously caught the attention of investigators. The vehicle's owner had washed it after the wedding, he said in order to sell it.
Sniffer dogs lost the scent from Maelys's cuddly toy in a car park outsidethe venue, raising fears she was kidnapped and whisked away by car.
Police have interviewed about 250 people since Sunday, including most of the 180 guests at the wedding, as well as several others who attended parties held the same night at a nearby bar and church hall.