The club confirmed the deal on Friday morning, though the length of the extension has not been disclosed.
The Uruguay international, whose previous contract was due to expire in 2026, has been one of Tottenham's most consistent performers since arriving from Juventus in January 2022 for 16.6 million pounds.
He played a pivotal role in Spurs' Europa League triumph last season and has continued to be a mainstay under new head coach Thomas Frank.
"I feel really good and I'm very happy to continue my story with this fantastic club," Bentancur told the club's official website. "My family are happy, I have fantastic friends and team-mates who work hard every day. I love this club and feel really good here.
"Winning the Europa League was a fantastic moment and we want to build on this now, to win more trophies."
Frank welcomed the news, calling Bentancur "a fantastic midfielder who can dictate games, link the play and also create and score goals." The Danish coach added: "I'm extremely happy that Rodrigo has committed his future to the club.
"It shows his belief in what we are building here and that we are starting a journey which we hope will be really special."
Tottenham, who sit fourth in the Premier League with 11 points from six games, have impressed under Frank's guidance but have faltered in recent weeks.
They have won just once in their last four matches in all competitions, drawing with Brighton and Wolves in the league and sharing the points with Bodo/Glimt in the Champions League.
The club now hope Bentancur's renewal can spark a return to winning ways when they visit Elland Road on Saturday to face Leeds United.
Nigeria international Samuel Chukwueze has expressed his excitement at rediscovering top form at Fulham, crediting manager Marco Silva for playing a crucial role in his resurgence.
Leeds completed a stunning comeback from 2-0 down to snatch a 3-3 draw against a reeling Liverpool and pile fresh misery on Arne Slot.
Manchester City secured a second successive Premier League victory at home against Sunderland, Chelsea were held scoreless away to Bournemouth while Tottenham managed to beat Brentford.
Aston Villa delivered a major jolt to the Premier League title race as Emiliano Buendía struck deep into stoppage time to seal a 2-1 win over Arsenal on Saturday.
