Mariano Ninonuevo was a sports shooter who competed in the 50-metre free pistol event at the 1964 Summer Olympics in Tokyo, Japan.
At 43 years old, he was 48th out of 52 contenders with total points of 501. The event was held at Asaka Shooting Range, Nezu Park in Asaka, Saitama on October 18, 1964.
