In their first game, they take on Montpellier HSC away from home at the Stade de la Mosson in France. This is by no means an easy match considering Montpellier are the defending champions, though they are struggling at the moment with just four points in five games.
It certainly doesn't help that Rene Girard's side lost their top scorer and Golden Boot winner Olivier Giroud, who of course moved to the Emirates this summer.
With Schalke and Olympiakos the other two clubs facing off in Group B, the Gunners will surely have the realistic goal of winning almost every game and they look to get ahead tomorrow in France.
Here are five predictions for their first Champions League fixture.