The body of the 29-year-old, who was walking her own dogs, was discovered near the town of Villers-Cotterêts.
She died after "several dog bites to the upper and lower limbs and the head," prosecutor Frederic Trinh said.
Tests on 93 dogs were being carried out in an attempt to establish which of the dogs were responsible for the attack.
Five dogs belonging to the woman were among those being tested.
An autopsy showed that the victim suffered dog bites to the head, torso and arms. Police said they had opened a manslaughter investigation.