The 29-year-old has been one of Spurs’ most potent attackers since joining the club from Bayer Leverkusen in the summer of 2015.
He has combined with devastating effect with Harry Kane in recent seasons, making them one of the deadliest duos in Premier League history.
The South Korea captain has scored 107 goals in 280 appearances across all competitions in his six years in North London but is yet to win a trophy to show for his efforts, losing one UEFA Champions League final and one Carabao Cup final.
“It was already a big honour to play here for six years, the club have showed me massive, massive respect and obviously I’m very happy to be here," said Son after putting pen-to-paper on a new contract.
“It’s like home, especially with the fans, the players, the staff. There was no decision. It was easy. I’m so happy to be here and will be so glad to see the fans again soon."
Spurs’ managing director of football Fabio Paratici added: “We are pleased to have agreed a new long-term contract with Heung-min Son as we move towards the start of a new season and a new chapter for the club with Nuno Espírito Santo.
“Everyone can see the real positive impact he has on the Club, both on and off-the-field, and we are delighted that he will play a part in what we are trying to achieve in the coming years.”
Son scored 17 goals in 37 Premier League appearances for Spurs last season.