Curtis Lazar, Nicholas Ritchie and Yan-Pavel Laplante had the other goals for Canada, which got 30 saves from goaltender Zachary Fucale.
Canadian head coach Todd Gill said opening the tournament with a win was a huge positive for the squad.
"We obviously have a long way to go but we're going to get better and better with each game and each practise," said Gill. "We have three in a row here and face Sweden (on Tuesday) and have to be better than we were tonight.
"We're a brand new club trying to learn systems and new players so it's going to take a little bit but it was a good start."
Canada has dominated the summer tournament since its inception, winning it 16 times since 1991.
Gill, who coaches the Ontario Hockey League's Kingston Frontenacs, said the Canadian team's strength is its offensive firepower.
"Our kids are buying in and we had a good cycle going and we got a lot of opportunities of it," he said. "We just have to start burying our chances."
Canada fell behind in the first period after Switzerland scored on the power play. But Lazar tied the score at 15:45 before MacKinnon, who is expected to be one of the top picks at the 2013 NHL draft, put the Canadians ahead to stay at 19:49.
Ritchie's power-play goal accounted for all the scoring in the second before Laplante cemented the victory with an empty-net goal at 19:46 of the third.
Gill said the Canadian team adjusted well to the larger European ice surface but had a harder time getting used to the officiating.
"We had nine penalties in this game and we really have to cut down on that," Gill said. "A lot of them were stick penalties where the defenceman has a man going wide and gives him that little tap that we're used to doing but it hits the other player's stick and we're in the box all night.
"It's frustrating but you can't let it get you down because they're going to call it all night long no matter what the score is."
The good news, Gill said, is that can be readily fixed.
"It's discipline," he said. "As a coaching staff we're going to have to put a plan in place where instead of chasing the guy and giving him a whack we play a turnover game where you turn the player over to someone who is closer to him."
Canada is in Group A with the Czech Republic, Finland and Slovakia. Russia, the U.S., Sweden and Switzerland make up Group B. The top two teams in each division advance to the semifinal round Friday.
The two winners will square off in the tournament final Saturday.
Canada will face Slovakia on Wednesday before having a well-earned day off Thursday. Gill said with such a condensed schedule, it's important a team be able to roll four effective lines to keep all the players fresh.
"You have to give everybody the opportunity to play," he said. "Tonight, for the most part, we rolled four lines.
"The thing I find is (coaches) don't really match up here, they just roll their lines and that's a bonus, I guess. If I see them throw a line that I think is considered their fourth line then if I get last change I'm coming back with my No. 1 line. But tonight I wanted to roll four lines to get everybody ready."Suggest a correction