Police in Villers-au-Tertre, near Douai, made the gruesome discovery using sniffer dogs.
All of the children are believed to have been born to the man and woman, who are aged around 45, said a source close to the inquiry.
“We searched the premises and the garden following a tip-off,” said a detective. “What is certain is that the new born babies all had the same parents.
“They were stuffed inside plastic bags and then buried. Six babies were found very quickly around the house, and the other two were discovered in the garden.”
The detective said that the parents were being held in Douai on suspicion of failing to report a crime, and the concealment of corpses.
The Douai prosecutor has opened a judicial investigation, and bail has been refused. Charges were expected this week.
Neither of the parents has been named.
Three years ago a 35-year-old woman and her boyfriend were arrested in Rouen, north-west France, after five dead newborns were found in their cellar.
All appeared to have been strangled at birth before being placed in plastic bags and hidden.
Such cases were reminiscent of the so-called “Seoul freezer babies” of 2006.
Frenchwoman Veronique Courjault was taken into custody on suspicion of killing her two babies and storing their corpses in a freezer in the family’s apartment in Seoul, South Korea.
Courjault, who had two living children, also admitted to killing a third child. She explained her actions by saying the pregnancies were unwanted.
In June last year Courjault was found guilty of triple murder and sentenced to eight years in prison.
Psychologists have since argued that “denial” is common among women who have had babies, and that the killing of a baby is caused by psychiatric problems rather than criminal intent.
Courjault’s husband, Jean Louis Courjault, was tried as an accomplice to the murders but found not guilty.
He said he never had any idea that his wife was pregnant because she kept the babies secret by wearing loose clothing.
Police are still digging up the garden of the house in Villers-au-Tertre, and a protective fence had been placed around the property.
“The search is still going on – both inside and outside the house,” said a police officer at the scene.
Villers-au-Tertre is a village in the far north of France, with a population of about 600. – Daily Mail