Bale struck from 30 yards with two minutes remaining after Sunderland had defended admirably to keep the score goalless for 88 minutes.
However, with Arsenal beating Newcastle United at St James' Park, Spurs will play in the Europa League next season.
Sports Mole has taken a look back to see whether Tottenham's win was a fair one.
On target 19
On target 4
Was the result fair?
Spurs will argue that the number of shots that they had justifies them winning the match, but Sunderland defended superbly and can count themselves unlucky.
Tottneham Hotspur's performance
On the whole, Tottenham played well without possessing a killer instinct in front of goal. 19 shots on target would suggest that they had Simon Mignolet making save after save, but the majority of his stops were comfortable.
Manager Paolo Di Canio demanded that his players perform with dignity in their final match of the campaign, and although he will be disappointed with the result, the Italian will be encouraged ahead of next season.
Sports Mole's man of the match
Gareth Bale: There wasn't any one player who stood out during the 90 minutes at White Hart Lane, so the award has to go to Gareth Bale for his stunning long-range strike that won the match. There were times when the Welshman cut a frustrated figure, but he continued to work hard to make something happen and he was rewarded with two minutes to go.
This wasn't one of Andre Marriner's better games, and he will come in for plenty of criticism for handing Bale a yellow card for simulation. It should have been a penalty for Spurs, and if they had scored that, the pressure would have been heaped on Arsenal.
Tottenham Hotspur: Tottenham's main objective for the summer will be to retain the services of Gareth Bale, which has become a little harder with them being unable to provide the 23-year-old with Champions League football.
Sunderland: Di Canio will be aware that he will have to strengthen his squad significantly if the Black Cats are to stay clear of the relegation zone next season.