Matsuyama turned professional in April 2013 and won his second professional tournament, the 2013 Tsuruya Open on the Japan Golf Tour. Five weeks later, Matsuyama won his third title on the Japan Golf Tour at the Diamond Cup Golf tournament. Following a top 10 finish at the 2013 U.S. Open, Matsuyama entered the top 50 of the Official World Golf Ranking. He won his fourth Japan Golf Tour event in September at the Fujisankei Classic. Matsuyama would win his fifth Japan Golf Tour event in December at the Casio World Open. The win also made Matsuyama the first rookie to lead the Japan Tour's money list.