He was drafted by the Calgary Flames.
The 18-year-old, who plays for the Charlottetown Islanders, entered the draft as the second-ranked goalie. He was also named top goaltender at the recent World Under-18 Championship.
McDonald started his first Quebec Major Junior Hockey League season with Acadie-Bathurst Titan and was traded to the Islanders on Dec.29.
McDonald stands six feet four inches and weighs 185 pounds and said he has started packing on weight for the big leagues.
Mason McDonald told CBC News last month that his favourite team is the Boston Bruins (currently the home of Brad Marchand, another Nova Scotian), but said he'll happily switch his allegiance to whichever team drafts him.