Hirayama made her international debut in 2005 at the FIS jumping in Sapporo . She immediately reached eighth place and was accepted into the A-team shortly afterwards. On March 1, 2006, Hirayama made her debut in Zaō in the Ski Jumping Continental Cup . Already in the first Continental Cup competition she reached the points. She also won Continental Cup points in all other competitions up to 2009. At the Junior World Championships 2007 in Tarvisio she reached the 22nd place in the individual. The 2006/07 season ended Hirayama as the most successful of her career so far in 36th place in the overall Continental Cup standings. In 2008 and 2009 she only competed in jumping in Japan. It only started again in Europe on January 23, 2010, but was unable to win any points in Schonach for the first time with 43rd place. At the Junior World Championships 2010 in Hinterzarten she reached 24th place in the individual. At the end of the season she competed again two competitions in Zaō and won again Continental Cup points. She took second place at the 2011 Winter Universiade in Erzurum , Turkey .
On March 3, 2012, she made her World Cup debut at a competition in Zaō . Since she never placed in the top 30 in the 2011/12 season , she did not receive a World Cup point and is therefore not included in the overall ranking. In jumping in Ramsau am Dachstein in the 2012/13 season , she jumped to 27th place and thus secured her first four World Cup points.