The 25-year-old, who is currently representing his country at the Confederations Cup in Brazil, has been linked with a move to champions Juventus.
But Moratti is eager to help new head coach Walter Mazzarri strengthen Inter's backline with new recruits rather than allow a key player to join their fierce rivals.
When asked if he had ruled out selling Ranocchia in the upcoming transfer window, Moratti told inter.it: "Yes, I think so, plus the defence is where we really need to strengthen.
"Ranocchia is one of the best in the country in that position, and he plays for the national team.
"We'll see who leaves and who might come in that would fit in with Mazzarri's system as well as what assets the club has at its disposal."
Ranocchia has made 62 league appearances for the Nerazzurri since leaving Genoa in January 2011 and the tall centre-back has played 10 times for Italy.