The European champions were drawn alongside Spurs, Borussia Dortmund and APOEL in Group H, but will have to wait until next month for their meeting with the Premier League side.
The 28-year-old said he may struggle to control himself if he nets a late winner when he faces his former club.
"I scored against Spurs in a pre-season game a couple of years ago and I didn't really celebrate then," Bale told the Daily Mail.
"I suppose it depends on how you feel on the day. If it's a 91st-minute winner, can you control yourself? That's the question."
Madrid begin their Champions League defence at home to APOEL on Wednesday, and are among the favourites to win the trophy for a third consecutive year.
On last month's group stage draw, Bale said: "I was in a meeting when the draw was made and my phone was going off constantly and I thought, 'something's happened.'
"I remember playing against Real Madrid when I was still at Tottenham and 'Crouchy' [Peter Crouch] being sent off after only 15 minutes and that killed the game for us.
"All my friends are still Tottenham fans. That is their team in the Premier League and I will certainly have a lot of ticket requests."