The North London outfit broke their club-record transfer fee to secure the signature of the German international for £42.5m from Real Madrid.
"I'm really excited," Ozil told the club's official website. "It's a perfect decision for me and and I'm looking forward to it all.
"Arsenal are well known for the strength of their technical game and their desire to play attacking football. I think I will fit perfectly into that. That's why I chose to sign for the club."