The 33-year-old Cesar joined QPR last summer and produced some impressive displays, although he was unable to save them from relegation to the Championship.
And he now looks set for a return to Italy, having made over 200 appearances for Inter during a very successful seven-year stint between 2005-12.
Cesar was recalled to the Brazil team last season and was between the sticks for their recent Confederations Cup triumph.
The Brazilians will host the World Cup next summer and Cesar is believed to be keen to remain in a high profile league, in order to boost his chances of remaining his country's number one.
QPR are thought to be open to his departure due to his high wage bill and he has been strongly linked with a move across the capital to Arsenal.
However, a loan move now looks on the cards to Napoli, who enjoyed a superb 2012/13 season, finishing second in Serie A, and who will be coached by Rafael Benitez this season.