Speaking about the decision, Gough said: "With sadness it's time to announce I am leaving the Ospreys by mutual consent. I have been at the region since 2007 and have enjoyed every minute of my time here. The welcome I had and the friends and memories I have made will stay with me forever.
"I've enjoyed on field success with the team and have also been lucky enough to help with coaching the young regional age grade players within the set-up who I believe will help take this region forward.
"I consider Swansea my home now. I wish everyone at the region the best of luck for the future."
Gough has proven to be one of rugby's stalwarts during a lengthy career which has seen him make 119 appearances for the Ospreys since signing in the summer of 2007. With his 92 games for the Dragons prior to that, he has made a total of 211 regional rugby appearances since 2003.
In total, he has made 480 first class appearances throughout his career, including 139 for Newport RFC, 57 for Pontypridd, 64 for Wales and a further nine with Wales A.
Ospreys Rugby Operations Manager, Andy Lloyd, commented: "Ian has been a tremendous servant to the region since signing in 2007, never giving anything less than 100 per cent to the Ospreys.
"Not only has he worn the jersey with pride, he's given his time to work with the next generation as a coach to help develop some of the young second rows that are now coming through the system.
"He leaves us with the best wishes of everybody at the Ospreys and with good luck for the future."