Made her professional debut in 2005. The following year she won her first championship and in 2010 she won her first major championship at the "Japan Women's Professional Championship Konica Minolta Cup".

From the 2021 season, she used N.S.PRO shafts, and in 2022, she won the championship again, making it the first time in 11 years a player has won this tournament twice. In the same year, she qualified for the Women's British Open and in 2024, she qualified for the U.S. Women's Open in Pennsylvania. Saiki continues to have a strong desire to challenge not only the domestic women's tour, but also overseas majors. Her efficient swing and the long distances she can hit with her driver are also appealing, and she continues to wow the gallery with the accuracy of her shots, which have produced a tour-record seven hole-in-ones. With N.S.PRO in her arsenal, she will continue to be admired not only by the gallery, but also by younger professional golfers.