Spurs face Lyon on Thursday night in the round of 32 and Gallas said that they are aiming to win as it is "important" to pick up some silverware.
"Tottenham want to win the competition, the Europa League, because it's very important for us to achieve something at the end of the season," Tottenham's official website quotes Gallas as saying.
"I would say that Lyon are a club in transition, a club which is in the middle of a rebuilding process, so as a result you have players who have got less experience - but that doesn't mean we can take this game lightly. We have to be very much on our guard and go all out to win."
Spurs and Lyon kick off at 8.05pm.