The 28-year-old spent the first two years of his senior career at the Veltins-Arena after emerging through the German outfit's youth ranks.
Ozil rejected a new offer in 2008 and instead moved on to Werder Bremen, however, before taking in spells with Real Madrid and Arsenal over the past eight seasons, but the Germany international has hinted that he would one day like to return to help them out of their 'slump of mediocrity'.
"Schalke is my absolute favourite club, I'm still a big fan," he told Funke Media Group. "After all, I grew up with Schalke. In terms of potential, Schalke is the number three for me in Germany after Bayern Munich and Borussia Dortmund.
"They have wonderful fans and a great stadium. It is a pity that they are stuck in mediocrity. This fantastic club deserves more. My family would be very happy about a return."
Ozil is out of contract at Arsenal at the end of next season, but he is not expected to be sold by the Gunners during the summer transfer window.