The 19-year-old striker is making his second consecutive appearance at the tournament.
Roy had eight points (3 goals, 5 assists) in seven games last year to help Canada win the gold medal.
The native of St-Georges-de-Beauce, Que., is having another stellar season with the Sherbrooke Phoenix of the QMJHL. He has 43 points (18 goals, 25 assists) in 26 games.
Roy was Montreal’s fifth-round pick – 150th overall – in the 2021 NHL Draft.
Fellow prospects Owen Beck and Riley Kidney were both cut.
The tournament will take place in Halifax, Nova Scotia and Moncton, New Brunswick from December 26 to January 5.