The Gunners are currently fifth and are vying with Chelsea and Tottenham for a finish in the top four.
Two of the three clubs are likely to finish with Champions League places while the other seems set for the Europa League, bar a late surge from Everton in sixth.
"We want to be at places like Bayern Munich again," Walcott told The Mirror. "It would be a tragedy for this team not to be in the Champions League.
"The way we played in Germany shows how much we have underperformed at times this season.
"It's been up and down. For the big occasions, we tend to turn up - it's just very frustrating.
"Since I've been at Arsenal, I've always been in the Champions League and I definitely want to keep it that way."