Rykiel, nicknamed the Queen of Knitwear, had been suffering from Parkinson's disease for some time before her death.
Born on May 25, 1930, Sonia started her career as a window dresser in 1948, with her first foray into design being when she knitted herself maternity dresses after marrying Sam Rykiel, the owner of a Paris boutique.
Rykiel made her breakthrough in 1962 with the so-called poor boy sweater, which had long sleeves and a fitted shape.
Nathalie Rykiel, managing and artistic director of the Sonia Rykiel fashion label, said: "My mother died at 05:00 this morning at her home in Paris from the effects of Parkinson's."
In her memory, check out some of the designer's pieces that made history: