Mason has been capped twice by Wales
Keith Mason will remain with Huddersfield until the end of the 2015 season after signing a new contract.
The 28-year-old prop forward is expected back in action soon after suffering a knee injury.
Giants coach Nathan Brown told the club website: "Keith is a hard-working player and that's something we've based ourselves on over the last few years.
"Keith works as hard as anyone, is a great trainer, has a great attitude and is always ready to put the team first."
Brown added: "In my time at the club Keith has always played an important role in the team and with the little additions he has brought to his game, he is definitely playing his best footy."
Mason has made 117 appearances for the Giants to date, scoring four tries.
We have an awesome base here now along with a great set up
He said: "I am very thankful for the club's faith in me and I'm planning to reward them with some good years ahead.
"There is a good nucleus of us on long-term deals and it is exciting to be around quality players going forward as we strive to be successful.
"We have an awesome base here now along with a great set up and I'm just glad to be a part of the club for the next four and a half years."
Mason has been on the sidelines since early April after injuring a knee in the 34-10 victory over Wakefield, but is hoping to return to action soon.
"I've looked after myself for the last six weeks through this injury and I can't wait to get back to playing as soon as possible as we come up to the important part of the season."