Hallyday, with his cowboy swagger and gravelly voice, was a “French Elvis” for hundreds of millions of followers, mostly if not all in his native country, where he sold more records than any other singer.
He had been fighting lung cancer, and also preparing yet another album recording and stage tour.
News of his death after weeks of frenzied speculation about his health, set social networks alight with tributes from fans, politicians and celebrities.
“For more than 50 years, he was a vibrant icon,” President Emmanuel Macron's office said in a statement.
Hallyday is credited with sales of more than 100 million albums over the decades.
While never earning stardom in the United States, where he lived in Los Angeles in later years, he won a legion of followers in France and elsewhere in the French-speaking world