The 21-year-old forward scored 115 points (41 goals, 74 assists) in 127 games during four seasons at Boston University, including 37 points (14 goals, 23 assists) in 32 games this season.
Harper, selected by Nashville in the fifth round (No. 138) of the 2016 NHL Draft, finished this season 15th among NCAA Division I skaters in points per game (1.16), tied for 18th in points and tied for 25th in assists.
"Patrick is a dynamic player and with his size (5-foot-7, 150 pounds) excels in the way today's game is played," Predators director of player development Scott Nichol said. "He's a fun player to watch; he likes having the puck on his stick, he likes to make plays and wants to score goals every game. He fits in well on the power play and uses his biggest on-ice attribute -- his hockey sense -- to his advantage."
Harper played for the United States at the World Junior Championship twice, finishing first in 2017 and third in 2018.
He had four points (one goal, three assists) in nine games with Omaha of the United States Hockey league in 2015-16.
