The award was presented virtually by Martin St. Louis, who won the Lady Byng Trophy three times during his Hall of Fame career.
"I think it's important to treat your opponents with respect but also play hard, between the whistles," said MacKinnon. "It's important that your coaches can trust you in key situations and you won't take a minor and put your team on the penalty kill so obviously, it's amazing to win this award given that some of the best players have.
"So to also win this is very humbling and exciting and I never thought I would win this one but it's cool and I'm very honoured."
MacKinnon finished fifth in league scoring with 93 points (35 goals, 58 assists) in 69 games while leading the Avalanche into the playoffs for the third consecutive season. The 24-year-old registered a career-low 12 penalty minutes, the second-fewest among the league’s top 25 scorers.
No other NHL forward averaged more time on ice (21:13) in 2019-20 while taking fewer penalties.
The award is voted on by the Professional Hockey Writers' Association.