"The time has come to say goodbye," Milito wrote on his Facebook page. "Unfortunately my time with Inter has reached its end. I have decided to try a new professional adventure."
Milito scored both goals in a 2-0 victory over Bayern Munich in the 2010 Champions League final in a glorious debut season that saw him score 30 goals in all competitions as Inter won Europe's elite club competition, Serie A and the Italian Cup.
However, the 34-year-old has struggled to replicate that form after being struck by a series of injuries.
This season he scored only twice in 17 league appearances but despite an inconsistent campaign he remains a fan favourite for his past exploits.
"I still don’t know what the future holds for me, but I still feel alive and have a burning desire to be an important player again," he added.
"I want to thank everyone who over the years at Inter I shared success and incredible joy with - the club, president Massimo Moratti, all the members of the staff and obviously all my team mates.
"The biggest thanks go to you the fans for all you’ve given me in these five seasons... I will carry you in my heart forever, you’ve been fantastic."
(Reporting by Terry Daley; editing by Josh Reich)
