Vitti’s death was announced by writer, director and politician Walter Veltroni on behalf of Vitti’s partner, Roberto Russo, with whom she had been since 1973. They married in 2000.
The film star, who shot to fame in the 1960s, had been battling Alzheimer’s disease for two decades.
Vitti was best known for her roles in films by director Michelangelo Antonioni, including L’Avventura (1960), Red Desert (1964), L’Eclisse (1962) and La Notte (1961).
Her co-stars over the years included Alain Delon, Michael Caine, Terence Stamp, Richard Harris and Dirk Bogarde.
After her string of films with Antonioni, she made a move to comedies and regularly worked with Mario Monicelli. This was in part due to the dissolution of her relationship with the Italian filmmaker.
She also worked with international directors Etore Scola (The Pizza Triangle, 1970) and Luis Buñuel (The Phantom of the Liberty, 1974).
Vitti made her last public appearance in 2002 while attending the French premiere of the stage musical Notre-Dame de Paris.
Russo revealed in 2018 that he was looking after Vitti at their home in Rome with the assistance of a caregiver.
Throughout her career, Vitti won five David di Donatello Awards for Best Actress, seven Italian Golden Globes for Best Actress and the Venice Film Festival Career Golden Lion Award.