The Australian prop, 34, has agreed a two-year contract with the Super League club who host Salford Red Devils tonight.
It is a key piece of business for head coach Richard Agar given how valued the former New South Wales State of Origin forward is. Prior joined last year from Cronulla Sharks and helped Leeds win the Challenge Cup final at Wembley.
With his work-rate, quality - defensively and in attack - as well as his vast experience, he has proved an astute signing.
Prior - now contracted until the end of 2023 - was vice-captain for the Combined Nations All Stars when they defeated England last month and is one of the most respected forwards in the competition.
“I am really pleased to have got it sorted as it has been going on for a little while now,” he said.
“I can focus on my footy now for the remainder of the season.
“The club offered me another year on top of the additional season I had an option for and I was glad to accept that as there are some exciting times ahead here at the Rhinos.It has been tough since we moved to England because of the Covid restrictions but there is light at the end of the tunnel now and I think the best is yet to come for me, my family and the Rhinos in my time at the club.
“I love the club. We have got a lot of good young guys coming through but we’ve also got some good senior blokes too.
“It’s a good club to be part of and I think it is a good time to be here.”
Agar added: “Matt has been fantastic for us during his time at the club and I don’t think you can underestimate how important this new deal is for the club and him.
“I know he has become a fans favourite and it will be great to see the reception he gets tonight when our fans return for the game against Salford.”
Rhinos director of rugby Kevin Sinfield said: “We are delighted to have agreed a new deal with Matt.
“It was a big decision for him especially with his young family.
“For anyone to be away from their loved ones is tough but during the global pandemic that has been particularly hard on all our overseas players.
“Matt has shown outstanding leadership with his actions on the field and he is a great example for our young forwards at the club.”
Meanwhile, Agar has warned his squad to watch their discipline after a fiesty 38-12 win over Salford Red Devils four weeks ago.
Rhinos were also heavily penalised during their defeat at Catalans Dragons last Friday.
Agar said: “Discipline is something we have talked about.
“We gave 11 penalties away last week, a number of them for high shots.
“Last week we lacked some composure and discipline and we just stopped doing some things together.
“We are making too many silly errors at the moment from an energy perspective.”