Brown made it clear that he will move from next season to Aberdeen as a player and coach at the same time.
And thus ends a long era for Celtic with Brown, who spent 14 seasons in its ranks.
“I would like to thank the Celtic management for the tremendous support over the past years,” Brown said on the official Celtic website. “We have enjoyed a great relationship and have always worked closely together to bring success to the masses.”
“I also thank the great Celtic coaches with whom I have had the good fortune to work with them, my many colleagues, and the Celtic fans who have supported me tremendously and have stood in my back for years,” he added.
He continued, “I always gave my best to the club and always wanted the best for the fans. We enjoyed great moments together, achieved many successes, dominated football in Scotland and experienced beautiful European nights.”
He continued: “Leaving this wonderful club is a big decision, because Celtic has been a huge part of my life for a long time, but it is a new opportunity for me. Celtic will never leave me and will always be in my heart.”
He concluded: “We still have work to do this season, of course, and I will be focused as much as it has always been to achieve successes for the fans.”
Brown, 35, joined Celtic in 2007 from Hibernian for 4.4 million pounds in a record deal between Scottish clubs at the time.
Brown played 604 games for the Celtic, scoring 46 goals and scoring 62 assists.
Brown has worn the captaincy of Celtic since 2010 and is the most representative player for the legendary Scottish club in European competitions in history.
Brown has won 22 titles with Celtic, including 10 in the Scottish League, which the team has won in the past nine seasons.
Brown played 55 caps for Scotland between 2005 and 2017, scoring 4 goals.