"The experiences over the last three years have been incredible in terms of my personal and coaching development," said Back.
"I am very passionate about what I do and I have thrived on the challenge over the past three years, however taking all things into account, I feel I have taken Leeds as far as I can.
"I am very proud of what Leeds Carnegie has achieved over the last three years against the odds and I wish Leeds all the success for the future."
Commenting on the announcement chief executive Gary Hetherington said, "Having met with Neil, he has informed me of his intention to move on at the end of the season to enable him to look for a new challenge.
"I would like to thank Neil for all his efforts during the past three years when he has helped move the club forward into a stronger position. In his first season, we won promotion and last season we defied the odds to retain our place in the Premiership. However, this year we have fallen short by the smallest of margins on the final day of the season and that comes as a disappointment to all of us."