Confirming his Ospreys exit, Johnson said: "Having initially committed myself to the Ospreys for three years, I've taken the time to consider my future plans and have advised the directors that while I intend to see out the remainder of my contract I will not be looking to renew at the end of the season.
"When I joined the region I had a remit to help set-up systems that would enable us to bring through home grown talent, coaches and players, a challenge I've thoroughly enjoyed getting my teeth into over the last three years.
"I feel that now is the right time for me to move on to other challenges but I remain 100 per cent committed to the Ospreys between now and the end of the season."
In the first season with Johnson in charge (09/10) the Ospreys reached the last eight in Europe and won the first ever Magners League Grand Final. They reached the semi-finals again the following season (10/11) and remain well placed to repeat that feat this season.
Andrew Hore, Chief Operations Officer at the Ospreys, commented: "It is a huge disappointment for us to be losing Scott at the end of the season, but we understand that he feels it is the right time for him to move on to other challenges having served the three years he committed himself to us for originally.
"He'll be sadly missed by everybody at the Ospreys when he moves on, but by informing us of his intentions at this early stage, it allows us to use this time to consider our next course of action and the options available to us as we plan for the future."
Ospreys Managing Director, Roger Blyth, added: "Scott is an innovative thinker who has worked tirelessly for the cause since joining the Ospreys. While he has brought silverware to the Liberty Stadium, and we hope that will be the case once again this season, the real legacy he will leave is the systems and structures he has helped to develop that will allow us to continue leading the way in Wales.
"Thanks to his efforts, working closely with Andrew Hore, there is now a clear pathway for young coaches and players alike within Ospreylia which allows them every opportunity to reach their full potential. The work he has put in over the last three years will ensure that the Ospreys continue to be known as a centre of excellence in development terms. In doing so, it will allow us to continue to compete at the top level, despite the ever increasing financial pressures we face both locally and from outside of Wales. We wish him the very best of luck for the future."