The mammoth, named Helmut, is 3.4 metres high, would have weighed four to five tonnes, and is thought to have been a contemporary of Neanderthal man.
Archaeologists were originally looking for Gallo-Roman artefacts when they set up a site at Changis-sur-Marne, north-east of Paris, but their attentions were diverted when they came across the giant tusks, Le Figaro reported.
“We very quickly realized, mainly because of the huge tusks, that this was some kind of elephant,” said Grégory Bayle, a scientist at the National Institute for Preventive Archaeological Research (Inrap).
“And after two weeks, we know that it was an adult animal, aged between 20 and 30 years, and which probably got stuck in a bog.”
Archaeologists also found flints beside the remains, suggesting the animal lived among humans. But experts doubt Helmut was hunted.
It is more likely that once the animal had died, humans took the meat from the carcass for food.
Only three discoveries of entire mammoth skeletons have been made before in France. The first discovery, the “Choulans mammoth”, was made in 1859.
Archaeologists will excavate the rest of the skeleton over the next ten days, when it will be sent to the national natural history museum for further analysis.
“I hope he will end his days in a museum,” Stéphane Péan, a palaeontologist at the natural history museum, told Le Figaro.