Kennedy was granted permission to negotiate with other clubs and has been released from the final year of his contract to take the new opportunity.
Sydney Roosters COO Football, Brian Canavan, said: While it is sad to be losing a player of Martys considerable experience, it would have been unfair of us to stand in his way, when due to salary cap restraints we were unable to match the other offer.
Marty first joined the club as a member of the Roosters SG Ball and Australian Schoolboys squad in 2007 and has been a popular clubman since making his NRL debut in 2009.
A consummate professional, Marty has played an important role in helping us re-establish our Club this season on and off the footy field. We thank him for his immense contribution to the Roosters over the years, and look forward to him being an integral member of our squad for the remainder of the year.
Martin Kennedy added: This is the only club I have known and it is heartbreaking to know that I wont be here next season.
Having said that, this is a wonderful opportunity for me to head home and be closer to my parents and brothers.
The Roosters have played such a big part in shaping me into the man I am today and Ive made so many lifelong friends here. I am determined to give my all for the remainder of the season and thank the Club and Members for their support over the years, he added.
Kennedy has played 65 NRL games to date since making his NRL and club debut in the opening round of the 2009 season (Roosters v Rabbitohs).