Michael Maguire has left the Rabbitohs effective immediately.
South Sydney have finished 12th the past two years and Maguire had two years left on his current deal.
It follows a board meeting on Tuesday at which Maguire fronted the members.
“Michael helped deliver the premiership title in 2014 and for this we will always be indebted to him. He led us to the premiership victory, the 2015 Auckland Nines win and the 2015 World Club Challenge,” club football manager Shane Richardson said.
“However, we feel it’s time for the club to go along a different path in terms of the leadership of the team and the direction the team is taking, and they are the responsibilities of the head coach.
“Michael also feels it’s in his best interest to head in a different direction in his coaching career.
“Michael is a great head coach and we believe he will go on to do a good job at another club, but as I said, it’s time for a change here at South Sydney.
“On behalf of the club’s members we sincerely thank Michael for his efforts over the past six years. He will always be remembered as the coach of our 21st premiership side, he helped bring this Club to a new level of professionalism, and we wish him and his family the best of luck for what lies ahead in his career and his family’s future.”
Maguire joined the Rabbitohs for the 2012 season.
Reports suggest he may head to the Super League or Gold Coast Titans.