Terry has been backed as Chelsea's captain and leader for next season by manager Di Matteo on the eve of the defender's trial for alleged racism.
England international Terry faces an accusation of making racist comments to QPR defender Anton Ferdinand at Westminster Magistrates' Court on Monday.
Terry denies the charge and managed to put in a series of impressive performances for England at Euro 2012.
His participation in the European Championship means Terry is not due to meet up with the Chelsea squad for pre-season training until the second week of their tour to America.
"JT has been tremendous over the years for his club and his country, and he was outstanding at the Euros," said Di Matteo.
"Hopefully, he will be the same for us next season. He is our skipper, our captain and our leader, and I expect him to be the same next season.
"In terms of how many years JT can keep playing, it varies from player to player and it depends on injuries.
"But providing you are mentally and physically driven by playing football you can go on.
"From my point of view, JT is one of the best central defenders in the country."