The striker took to his personal Twitter and Facebook accounts to break the news to his followers, drawing to an end speculation linking him with a move away from Germany
The 29-year-old's future had been shrouded in doubt recently, and had been strongly linked with a move to Liverpool as Brendan Rodgers attempted to reunite the Dutchman with former Ajax team-mate Luis Suarez.
However, the Netherlands international has revealed he has put pen-to-paper on fresh terms to keep him at Veltins-Arena for another three years.
Huntelaar broke the news via his personal Twitter account, telling his followers: "I'm very happy to share this great news with you.. I've signed a new contract with @s04 until 2015..!!"
He then added on his Facebook page: "I want to thank all the Schalke fans for their patience over the past period. From the beginning I’ve had a good feeling with the club and the fans.
"I believe that we can achieve beautiful things in the Bundesliga and Champions League. I'm proud that I can be part of this beautiful club."
Club general manager Horst Heldt added his delight that the striker's future had finally been put to rest.
"Together with Klaas-Jan, we had originally targetted next month to enter the crucial stage of talks," he told the club's official website. "The exchange on the subject [of the contract] in the past few months never completely broke down.
"Above all, I am pleased that Klaas-Jan is now a clear signal for the entire club for the second half of the season."