She qualified to the 2012 Summer Olympics as a member of the top-ranked Asian team. In the individual event, she defeated Hong Kong's Lin Po Heung in the first round, then lost 8-14 to five-time Olympic champion Valentina Vezzali of Italy. In the team event Japan was crushed 17–45 by Russia in the first round and placed 7th after the ranking matches. Nishioka fenced only against Russia.