The former Batley Bulldogs player joined Rovers ahead of the 2018 campaign and has now signed a two-year extension deal, keeping him at the club until the end of 2021.
He scored a superb try in Featherstone's 38-18 win over Sheffield Eagles last weekend, and has made a total of 14 appearances in 2019.
"I'm delighted, it has come around pretty quickly," said Harrison.
"I'm really enjoying my time here and I can't think of a better place to spend two more years.
"I've learned a lot this year, especially under Ryan, who's been great with me.
"When the opportunity came to stay under a coach like him and a club like this, I couldn't say no to it".
Harrison is the son of Featherstone Rovers, Great Britain and England player Karl Harrison.
The 22-year-old was named the Batley 2018 Coaches' Player of the Year and made 58 appearances for the Mount Pleasant club between 2016 and 2018.
"He's got a really big future ahead of him," added head coach Ryan Carr.
"He has really impressed here on and off the field and the boys love playing with him.
"I've been really impressed, he's had a few injury setbacks along the way, but he's worked hard to get back on the field and he's starting to reap the reward for it now".