Reece, 21, missed the last few months of the 2012 season for personal reasons, and played for Cardiff rugby union club in September.
He told the club’s official website: “I’m looking forward to coming back to the Scorpions and can’t wait to resume training.
“I’d like to thank our coach Dave Clark for giving me the opportunity again and I won’t let him down.”
The Wales international has scored 11 tries and 72 goals in 29 appearances for the Scorpions to date.
Head Coach Clark added: “I’m delighted that Lewis will be playing for the Scorpions again in 2013. His pace with the ball and his goal-kicking skills will be an integral part of our season and I know he’s going to do a good job for us.
“I know he’ll want to keep up his record points tally, especially with Steve Parry not far behind him now!”
Parry is just 12 behind Reece’s record, having scored 176 points in his three seasons with the club.