Confirmation of his omission has cast further doubt over his future in north London and seemingly underlined the notion he is not in manager Mikel Arteta's plans.
It's been seven months since Ozil last featured in a competitive match for the Gunners.
The club attempted to move him during the summer, but Ozil said he intends to see out the final year of his contract, which pays him a club-high £350,000 a week.
Fellow Arsenal outcast Sokratis Papastathopoulos was also left out of the squad that will take on Molde, Rapid Vienna, and Dundalk in the Europa League group stage.
Arsenal also omitted teenage defender William Saliba, who could be set for a loan to give him regular playing time.
While Ozil has yet to feature in a Premier League match this season, his future at Arsenal will be clearer when the deadline for teams to submit squad lists for the top flight arrives on Oct. 17. If he's excluded, Ozil - who joined Arsenal from Real Madrid for £42.5 million in 2013 - is prohibited from appearing in the Premier League until January.
Ozil attempted to endear himself to Arsenal fans earlier this week when he offered to pay the wages for the man who plays club mascot Gunnersaurus after it was revealed the club was severing ties with him.
Meanwhile, new Arsenal midfielder Thomas Partey, who joined the Gunners on Monday from Atletico Madrid for €50 million, is included in Arteta's Europa League team.
Arsenal will kick off their European campaign against Rapid Wien on Oct. 22.