Coloccini had been linked with a move to Crystal Palace, and a link up with former United boss Alan Pardew, so the news comes as a welcome boost on the eve of the new season.
Coloccini, 33, told the club website: “I am very happy to have signed a new contract. I have been here for seven years and I love this club. I feel part of the family at Newcastle United.
“Headlines and speculation are normal when a player only has one year left on their contract, but the club have shown they want to keep me and that has made me feel very happy and very proud.
“I am also very happy to continue as the captain of this football club. Captaining Newcastle makes me so proud. I am not from this city or this country, and so to be given the responsibility of wearing the armband every week is a very special thing.”
United head coach Steve McClaren added: “From day one at the club, Fabricio has been a stand-out character and I’m delighted we have secured his future with us.
“Once we sat down together to iron things out, I knew straight away his heart was with the club and the new contract was agreed very quickly. Fabricio is my captain. He is a leader, hugely respected throughout the club and a top-class player on top of that.”