The cause of his death was not disclosed.
ANSA said the "Padre Pio," "Cuore" and "La Guerra e Finita" filmmaker was known for a series of high-profile legal disputes, including a $41 million bankruptcy case.
"My husband was sick. This court case broke his heart, he was exhausted," the Italian news agency quoted de Nichilo as saying.
The ex-chairman of the Rizzoli publishing empire was charged last February with alleged fraudulent bankruptcy, involving his company Audiovisual Tiber, and had been under house arrest since then.