The former England captain has left the East Yorkshire club following an eventful three years in the position.
Peacock joined Rovers after ending his decorated playing career as a Grand Final winner once more with Leeds Rhinos in 2015.
He was brought into to help restructure the club’s football department and improve standards and quickly made some big decisions.
Head coach Chris Chester, for instance, was sacked just three games into the 2016 season, a year that ended with Rovers relegated and Peacock actually coming out of retirement.
However, with head coach Tim Sheens installed, he remained at Rovers last year in their successful bid to win an immediate promotion back to Super League and has seen them retain top-flight status via the Qualifiers this time around.
Peacock has been operating on a part-time basis for the last two years and has a number of other roles including England football manager and working a BBC pundit.
“I’ve had three fantastic years here during which I’ve learned a lot about myself,” said Peacock.
“I’ve learned a lot about Hull as a city and I’ve learned a lot about Hull Kingston Rovers.
“It’s become a part of me as much as Leeds has and I will remain involved here by working on leadership development programmes with the likes of Sewell’s and delivering health and wellbeing programmes for NHS Hull CCG.
“But in terms of Hull KR, I think now is the right time to move on. The club is in good hands with a squad that just needs to believe in themselves and a rugby department with some very good staff in key roles.”
Peacock, 40, continued: “I’m thankful for the opportunity I’ve had here and I’m grateful to the board of directors for giving me the chance to work alongside some great people – staff, fans, players and sponsors – who really care about the club. “I’d also like to personally thank Neil (Hudgell) for his belief in my abilities when bringing me into the role and also for his support over the three years that I’ve been here.
“That first year was a real baptism of fire and culminated in me coming out of retirement, something which I never thought I’d do.
“Thank you for allowing me to part of your history and I’ve got really fond memories of pulling on the Hull KR shirt for all but those final 10 seconds.
“It was a dark day to get relegated but the way that everybody rallied around over the next six weeks showed to me just how special this club is.
“I’m certain that under the new format the club has a real chance to make further progress up the Super League ladder and I wish everybody at Hull KR the best of luck in doing that.”
Hull KR chairman Hudgell added: “I’d like to place on record our thanks to Jamie for all he has done for the club during his time here.
“He’s made some very high profile contributions by helping to bring in the likes of Robbie Mulhern, now a full England international, Danny McGuire and Joel Tomkins, to name a few.
“But he’s also been at the heart of improving our systems and structures behind the scenes, bringing in a strong backroom staff to work with Tim and improving facilities and standards.
Hudgell continued: “Following our relegation, Jamie moved into a part-time role at the club to coincide with him pursuing a range of other activities with Tim taking a more active involvement in all areas of the football department.
“During our relegation year Jamie did not hesitate to throw his hand up and play again when times were tough.
“That typifies his character and is something I will never forget.
“Over the last three years I’m honoured to say on a personal level we have become good friends
“After our return to Super League and then our survival in the Qualifiers this year, it seems a natural point for Jamie to continue to develop his portfolio of interests away from the club.
“He will remain in regular contact with us as an ambassador and advocate for us. We obviously expect he will continue to be hugely successful with his future ventures.”