The 33-year-old Australian had been playing at the top level of French rugby league after two seasons in Super League with Catalans Dragons.
He has also played in the NRL for Cronulla Sharks and Penrith Panthers.
"He's a whole-hearted player and puts his body on the line," head coach Tony Smith told the club website.
Pomeroy added: "I have been playing in the French competition but I was always keen to play in Super League again.
"This opportunity at Warrington came up and I think is perfect for me. I'm excited, it feels like I'm making my debut again."
Super League side Warrington Wolves have signed Lezignan Sangliers centre Ben Pomeroy on a deal until the end of the season.