"She would have been 95 on 21 October," she added. "My mother left peacefully."
Last year Ms Bettencourt was ranked the richest woman in the world with a fortune of $39.5bn (£29bn), by Forbes magazine. It made her the world's 14th richest person.
In a statement, L'Oréal chairman and CEO Jean-Paul Agon expressed his condolences to the family and said: “We all had a deep admiration for Liliane Bettencourt who has always watched over L'Oréal, the company and its employees, and who was very attached to its success and development.
She was rarely seen in public since she left the board of the French company in 2012, but continued to make headlines after members of her team were charged with exploiting her as her mental health deteriorated.
A French celebrity photographer was sentenced to two and a half years after Ms Battencourt showered him with gifts including Picasso paintings, life insurance funds and millions of euros in cash.
Born in Paris, she was the only child of Louise Madelaine Berthe and Eugene Schueller, who founded L’Oreal. Her mother died when she was just five years old, leaving her to form a close bond with her father.
She joined the family business when she was just 15, before inheriting the empire when her father died in 1957.
She married a French politician Andre Bettencourt, who served in the cabinet of the French government in the 1960s and 1970s. He had been a member of La Cagoule, a violent French fascist pro-Nazi group that her father, reportedly a Nazi sympathiser, had funded and supported during the 1930s.The couple had one child, Francoise, in 1953.
Her daughter said in her statement: “In this painful moment for us, I would like to reiterate, on behalf of our family, our entire commitment and loyalty to L’Oreal and to renew my confidence in its President Jean-Paul Agon and his teams worldwide.”
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