The 31-year-old Belgium midfielder, who would have been out of contract in the summer, has signed a three-year deal, according to his new club.
Dembele joined Spurs from Fulham in 2012 and made 250 appearances, but had not played since November 3 due to an ankle injury.
A Spurs statement read: “We have reached agreement with Chinese Super League side Guangzhou R&F for the transfer of Mousa Dembele, subject to international clearance. We wish Mousa all the best for the future.”
Dembele, who was part of the Belgium squad that finished third at the World Cup, arrived in England with the Cottagers in 2010 after joining from Dutch club AZ Alkmaar.
After seven goals in 74 games for them, he joined Spurs for £15million.
We have reached agreement with Chinese Super League side Guangzhou R&F for the transfer of @mousadembele, subject to international clearance.— Tottenham Hotspur (@SpursOfficial) 17 January 2019
Dembele struck 10 times for Tottenham, with his last goal coming in a 4-0 win against Bournemouth in 2017, and he played a key role in their rise under boss Mauricio Pochettino.
The midfielder said in an interview shown on Spurs’ Twitter account: “I’ve always had a good experience here. I go away with an unbelievable feeling and with a certain love for the club.
“You always want this, because you have a long period at a club, you have a lot of love for the club but sometimes you separate in a bad way and I don’t feel that way.
“Even the reaction I’ve had from the supporters, everyone is positive with me. They’ve wished me a lot of luck and happiness. The club is part of my family now.”
Spurs defender Jan Vertonghen said: “You have to ask the players who have played against Mousa or with Mousa to get the appreciation he deserves.
“Sometimes it made me angry a bit that people talked about the best midfielders in the Premier League and haven’t named Mousa, but I feel like he got that appreciation over the last two years.”
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