The Gunners are facing a campaign without Champions League football for the first time in two decades after finishing down in fifth place in the Premier League last term.
Giroud, who is likely to start the Group H opener, believes that taking the competition seriously is imperative if Arsenal are to win silverware.
"We need to keep the focus high and always improve ourselves," he told reporters. "It's always nice to have good players alongside you and to push you forward, so trust me, we've got a very good team on paper tomorrow.
"If we play well and we play our game and we are very focused on this Europa League, we want to go and win it, we are very ambitious and I am looking forward to the game tomorrow."
Giroud also confessed that he considered quitting Arsenal during the summer due to a lack of playing time in 2016-17.