The London rivals meet at Wembley on Sunday in a bid to reach the cup final, with the pair playing out a 0-0 draw in the league at Stamford Bridge recently.
Despite an inconsistent run of form for Tottenham of late, Bale feels his side can beat the Blues this weekend.
“Obviously we’ve got difficult opposition in Chelsea,” he told The Sun.
“They’re a great side, have done really well in the Champions League and it won’t be easy, but I think if we are on our game on the day, then we can reach the final because I feel we have the better team.
“We played very well at Stamford Bridge recently, it ended goalless but we had the better chances on the day and we probably should have won the game.
“That will give us plenty of confidence going into this match,” he confessed.
The winner will play either Liverpool or Everton in the final.
By Gareth McKnight