The high school phenomenon made his summer league debut with the Cleveland Cavaliers and led his team to a 107-80 romp over the Orlando Magic.
James, playing mostly at point guard, had 14 points, seven rebounds and six assists in 23 minutes. He had 10 of his points in the opening half, including a dunk for his professional points.
The 6-8, 240-pound James, the second high school player taken with the top pick, will be in Orlando for three games. James and the Cavaliers will participate in the Boston summer league, starting next week.