Aoki competed for the women's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with her teammates Mayu Kida, Satomi Kubokura, and Asami Tanno. She ran on the anchor leg of the first heat, with an individual-split time of 52.64 seconds. Aoki and her team finished the relay in last place for a seasonal best time of 3:30.52, failing to advance into the final.