Clarkson, 25 has played almost 150 senior games, and spent time at Widnes on loan in 2015. He has secured a release from the final year of his Headingley contract to join the Robins.
“The club has a really bright future and I can’t wait to be a part of improving on the success of this year in reaching the Challenge Cup Final and going seven from seven in the Super 8s,” Clarkson told the Robins’ official website.
“Bouncing back after the final the way they did shows great character from the players and staff and I’m looking forward to adding to that.
“I spoke to Jamie Peacock quite a bit and he was a big influence on my decision to sign for Rovers, but I also spoke to Chris Chester and Willie Poching, who was my academy coach at Leeds, and they all had positive things to say.
“It’s done me the world of good this year to get some quality game time and play big minutes week in, week out at Widnes and that will stand me in good stead for at least the next three years at Hull KR.”
Rovers coach Chris Chester belives that Clarkson will alleviate the loss of Tyrone McCarthy from the Robins’ back row in 2016.
“Chris will be an ideal replacement for Tyrone McCarthy in our squad for next season and I’m really looking forward to working with him,” he said.
“He came through a good system at Leeds Rhinos and has done well with Widnes this year. He’s strong defensively, is very consistent and everybody who has worked with him has spoken positively about how he conducts himself on and off the field.
“He’s got his best years ahead of him but he has plenty of experience for a player his age and has played in some big matches during his career.
“We’re excited to have him on board and are pleased he sees his future here at Hull Kingston Rovers for the next three years.”