During the 2014–15 JGP series, Yamamoto won silver medals in Courchevel, France and Tallinn, Estonia, which qualified him to the 2014–15 JGP Final in Barcelona, Spain. Ranked first in the short program and third in the free skate, he finished second overall, behind Shoma Uno and ahead of Alexander Petrov. Nationally, he was the junior silver medalist, behind Shoma Uno, and finished 6th at the senior event. At the 2015 World Junior Championships, Yamamoto placed 7th in the short program and 3rd in the free skate to win the bronze medal in his first appearance at that competition.