Nugent-Hopkins, a center with the Edmonton Oilers, missed a chunk of time earlier this year with two separate shoulder injuries, but still finished with 52 points (18 goals, 34 assists) in 62 games.
Nugent-Hopkins was the No. 1 pick in the 2011 draft, and only turned 19 in April.
Henrique, a center with the New Jersey Devils, had 51 points (16 goals, 35 assists) and a plus-8 in 74 games.
"It's well-deserved," Devils goalie Martin Brodeur, who won the award in 1994, said to The (Newark) Star-Ledger. "The Calder is one of these trophies that is once-in-a-lifetime. It's one year and that's it. For you to be part of a group of top rookies is kind of nice to get recognized. He's in the top three regardless of what happens."
Landeskog, a left wing with the Colorado Avalanche, also had 52 points (22 goals, 30 assists) and played every game this season, finishing with a plus-20.
"He's a rookie, but he plays like a veteran out there," defenseman Shane O'Brien told NHL.com. "He acts like a veteran."
The winner will be announced during the NHL awards show June 20 in Las Vegas.