Justin Melton played high school basketball at Tabb High School in Yorktown, Virginia. After playing one year of junior varsity basketball, Melton played three years of varsity basketball, capturing Bay Rivers District 1st Team Honors in his junior and senior seasons. In his senior season, he was awarded Bay Rivers District "Player of the Year," along with 1st Team All-Region and All-State honors. Melton also excelled in track and field, placing 2nd in the Virginia High School AA State Track Meet in the triple jump event with a distance of 45 feet 6 inches.
College
Melton studied and played basketball on a full scholarship at Mount Olive College, in Mount Olive, North Carolina where he was very successful. Justin was a very tough player in college and was the leader and motor of the team for the last 3 seasons. He is extremely athletic can finish strong at the rim. He shot over 40 percent from the 3-point line in his senior year. Melton possessed above-average athleticism for a person of his size and was very quick. He is also featured on his college's official website because of being featured on a Yahoo! Sports article. He played more than 20 minutesa game in his college years.
He played in Brazil for the AABI CLineSP Artur Nogueira, made great games being fundamental for the conquest of the Paulista championship, but the team went bankrupt and he was waived.
Melton was picked 13th overall by the Mixers in the 2013 PBA draft. Melton was noticed as one of the most athletic players in his draft class, and he showcased that athleticism very fast with his teammates. Though measured at just 5-foot-9 in socks, Melton finished with several rim-rattling slams during practice. His energy was also on display on defense. Melton struggled in his first conference, the 2013–14 PBA Philippine Cup, due to injuries on the finger, but bounced back and even won the Best Player of the Game honors. He shocked the whole PBA, by winning the 2014 PBA All-Star WeekendSlam Dunk Contest held in the Mall of Asia Arena. He and Rey Guevarra had a head-to-head matchup on that battle, they have been tied for three rounds on the championship round, at last, they have been declared co-champions, because the process is going on and on. He has a high vertical leap, which allows him to jump very high despite of his 5'9" height. Melton is also a decent outside shooter, who shot at 67% in his first season.
