Vincent Lambert, 42, had been in a persistent vegetative state since a motorcycle accident 11 years ago.
Doctors began taking him off life support last week after a final ruling by France's highest appeals court.
Euthanasia is illegal in France, but doctors are allowed to put terminally ill patients into deep sedation.
Mr Lambert's case divided both the country and his own family, sparking demonstrations on the streets of Paris.
His nephew said he had died at 08:24 (06:24 GMT) on Thursday, nine days after his feed was removed.