The 20-year-old has been in excellent form this season, sharing his duties between the Club’s Intrust Super Premiership and Holden Cup sides.
Marsters, a talented back-rower, represented the Junior Kiwis earlier this season and also played a Test match for the Cook Islands last year.
The Mount Albert Lions junior has scored a total of 12 tries in 23 matches this season, across both the Intrust Super Premiership and Holden Cup.
The representative forward will join the full-time NRL squad next year, with his new deal securing him at Wests Tigers until the end of the 2018 season.
Marsters expressed his excitement to remain at Wests Tigers, where he will continue push for a place in the NRL side.
“It’s really good to re-sign because I wanted to stay at Wests Tigers,” he said. “I wanted to show my loyalty to the Club because it has been really good here and I’m enjoying my training.
“I feel as though the Club gave me a chance and I want to try and pay them back.
“There are other things to take into account like my family is really close here and we’ve based ourselves around here so it’s good to stay.
“Going up to the Intrust Super Premiership side has been really good for me, I was lucky enough for Paul Stringer to call me up a couple of times and I’ve enjoyed that challenge.
“It’s going to be massive having a full pre-season in the NRL squad and learning off guys like Chris Lawrence – I’m really looking forward to taking a few things on board from experienced players like him.
“For now though I’m focussed on finishing this year on a positive note with the Holden Cup team and leading into pre-season I want to start strong and really earn my stripes,” he said.