The new deal will keep the 26-year-old at White Hart Lane until 2015.
“I am obviously delighted that the club wants me to stay for another five-and-a-half years,” said Dawson.
“I was at Nottingham Forest from a young age and stayed for a long time but then Tottenham came along and I was keen to further my career and play in the Premier League.
“I have loved it here ever since I first signed and so it was an easy decision to extend my stay at the club, I never hesitated.
“This is a club that wants to be fighting to finish in the top four on a regular basis and challenging for silverware.
“That is what the football club is all about and everyone here shares those ambitions.”
