Bale sustained the injury during Madrid’s 2-1 win over Sporting Lisbon in the Champions League on Tuesday night.
Scans have shown that Bale has damaged the peroneal tendon in his right ankle and will be out for two to three months.
The European champions confirmed the winger will undergo an operation next Tuesday at the King Edward VII Hospital in London.
“The Real Madrid Sanitas Medical Services have decided that Gareth Bale will undergo an operation following the traumatic dislocation of the peroneal tendons of his right ankle,” read a statement released by Real Madrid on Thursday.
“The operation will take place at King Edward VII Hospital in London on Tuesday 29th November by doctor James Calder, under the supervision of the club doctors Jesus Olmo and Mikel Aramberri.”
Bale will now miss a number of key matches for Real including this weekend’s league game against Sporting Gijon as well as a midweek Copa del Rey tie against third-tier Cultural Leonesa.
Most importantly, however, the Wales forward has been ruled out of the crucial trip to Barcelona on December 3.
Zinedine Zidane’s side currently hold a four-point lead over their rivals at the top of La Liga but will be without the Welsh forward for the game at the Nou Camp.