Harrison (6-6, 210) went undrafted in the 2015 NBA Draft and joined the Charlotte Hornets at the Orlando Pro Summer League. The Hornets signed him to a mulit-year contract on July 14, 2015. In two seasons with Charlotte, Harrison saw action in 26 games and averaged 0.7 points and 0.7 rebounds in 4.2 minutes per contest. He was waived by the Hornets on January 3, 2017.
This season, Harrison is averaging 18.7 points, 4.4 rebounds, 1.6 assists and 26.9 minutes in 41 games while shooting .437 from the floor, .425 from behind-the-arc and .839 from the foul line with the Reno Bighorns of the NBA G-League.