The 19-year-old striker, who made his first-team breakthrough this summer, has made one start and six substitute appearances for Neil Warnock's side this season, scoring his only goal in the home win over Nottingham Forest in September.
"I'm glad to be tied down and commit my future here," Poleon told the club's official website. "I know I'm going to be here for a number of years now and I can work to that and hopefully push on."
Poleon, who came through the club's Thorp Arch Academy, scored twice in eight appearances while on loan at Bury earlier in the season.
"When I started the season I was happy to do well and scoring was a bonus," he added.
"The loan was all about me getting experience and that was a bonus doing well at Bury, so it's worked really well.
"I can only thank the gaffer here for the faith he has put in me. I'll keep working hard and hopefully I can shine and do well."
- Sports & Recreation