Germany international Ozil signed for the Emirates Stadium outfit from Real Madrid on transfer deadline day for a club-record fee and Mertesacker is delighted to see the 24-year-old move to London.
The pair played together at Werder Bremen earlier in their careers and are team-mates at international level.
And Mertesacker believes Ozil will adapt quickly to life in England, while helping the club challenge for trophies this season.
"I think that Arsene Wenger will get the best out of him," he said following Germany's 3-0 FIFA World Cup qualifying victory over Austria on Friday. "I think he will fit in.
"He suits us and we're really looking forward to playing with him and to be his team mate.
"We need players in every position - maybe two or three players, they can rotate and change position.
"We need to be dangerous up front and with him we are more dangerous."
Ozil could make his Premier League debut in Arsenal's trip to Sunderland on August 15 following the international break.
‘Even though it was late in the game, the Arsenal fans started singing my name. It felt like the moment I announced myself as a professional footballer’: Ex-Gunners star recalls scoring first senior goal as a teenager at Highbury
'I started to drive myself crazy': Former Manchester United midfielder explains why it all went wrong for him under Erik ten Hag
