Marie-France Pisier's lifeless body was discovered in the early hours of Sunday by her husband, Thierry Funk Brentano.
Officials in Toulon, near the couple's villa in Saint-Cyr-sur-Mer, have launched an investigation to determine the cause of death, but foul play is not suspected.
Marie-France Pisier began a career as an actress in 1961 when she was cast by director Francois Truffaut in short film "Antoine and Colette".
She shot to fame and became recognised as a star of the New Wave era, going on to work with filmmakers such as Luis Bunuel and Andre Techine.
The star scooped two best supporting actress honours at the prestigious Cesar awards - the French equivalent of the Oscars - for her work with Techine in "Cousin, Cousine" (1976) and "Barocco" (1977).
Her other notable films included 1982 comedy "L'as des as" and 1978 romantic thriller, "The Other Side of Midnight".
Pisier was due to appear at the Cannes Film Festival in May to honour top French actor Jean-Paul Belmondo, her co-star in "L'as des as".
French President Nicolas Sarkozy has paid tribute to Pisier, hailing her as "a supreme elegance born from the most perfect simplicity".