Chiellini has been linked with the likes of Manchester United, Bayern Munich and Real Madrid in recent months.
“I am happy to stay and help the team become great again,” said Chiellini.
“It will be a year of sacrifice. We must start from zero and reconstruct the base but this is normal after what happened last year.
“A managerial cycle has ended, some players have changed, there is much renewal going on and it is normal that time is needed. Three years ago, we would have hoped to be on a different level. Last year, we thought we could do well and win something but we know how things went.
“Now we must examine our conscience, understand where we went wrong and work in order to improve … the supporters must understand it will be a year of reconstruction.”