The Ireland and Lions legend has been ruled out for the season with a shoulder injury and will miss all of the Heineken Cup holders campaign which kicks off with a trip to Montpellier on Saturday.
The Irish province will travel as favourites to France but will be aware Montpellier, who were the surprise package of last season's Top 14 and only narrowly lost out to Toulouse in the championship final, will view the Dubliners as the perfect big scalp.
Galthie, though, has downplayed how the influence of O'Driscoll will be missed by the two-times champions of Europe.
"Brian O'Driscoll won't be in the team, but they have so many talented players we do not focus on the absence of Brian O'Driscoll," said Galthie. "It's not a matter of interest for us because we know whoever plays instead of Brian O'Driscoll will be a top player."
"I'm trying to manage my team to win the game because in the Heineken Cup you have to win your home games to qualify. We're not just looking to turn up and see how we play, we really are focusing on doing everything we can to win this game."
"Leinster have developed the ability to play an international game and so for us Leinster is the best team in Europe at the moment. They really play a wide game, full-scale, no limitations and at full speed.
"I am very impressed by the way they play the game. Playing against Leinster will give us the opportunity to learn if Montpellier is on the same level, close to the highest level or if we have a long way to go to reach the top."