Hiruta Mizuli was born on April 12, 1996, in Japan. Before turning pro, she had an extensive amateur career.
Hiruta got into boxing while she was attending the Okayama Technical High School. She continued to train while at the JSDF Physical Training School.
According to news stories, Hiruta was able to reach the finals of the 2016 All Japan Women’s Championships, competing in the flyweight event, but was defeated by the 2014 World Championships bronze medalist Madoka Wada in the final bout of the tournament. Hiruta participated in the next year’s All Japan Women’s Championship as well and although she was able to reach the finals for the second consecutive year, she once again suffered a loss at the hands on Madoka Wada.
Hiruta won the gold medal in the flyweight event of the 2018 All Japan Women’s Championships and in the featherweight event of the 2019 All Japan Women’s Championships. She furthermore competed at the 2018 World Championships, but lost in the opening round of the tournament. Hiruta ended her amateur career with a record of 29–16, with 13 victories coming by way of stoppage.
Hiruta made her professional boxing debut against Nanae Yamaka on October 15, 2021, winning the bout by a six-round unanimous decision.
Some of the highlights of some of her fights: Hiruta also fought Terumi Nuki in April 2022 in an eight round bout, and she won an eight-round unanimous decision. Another noted bout was against Hinami Yanai where they fought for the vacant Japanese flyweight championship. Hiruta won the fight by unanimous decision.
In December of 2022, Hirulta fought Kanako Taniyama, Hiruta won the fight by a unanimous decision. With that fight Hiruta was named the 2022 “Female Fighter of the Year” by a Japanese media members by vote.
In a world title bout, Hiruta won the WBO championship defended her belt against Casey Morton in June of 2023, winning by a KO. In a second defense of Hiruta’s WBO defense, in January 2024, she defeated Ji Hyun Park by a stoppage by TKO.
Hiruta made her third WBO championship defense against Maribel Ramírez at Commerce Casino in Commerce, California, USA, on January 17, 2025. She won the fight by an eighth-round unanimous Technical decision after Ramírez had been cut from an accidental head clash.
Again at Commerce Casino, she defeated Carla Merino by unanimous decision to retain her title for a fourth time on May 17, 2025.
Hiruta defended her title against Naomy Cárdenas at Chumash Casino in Santa Ynez, California, on August 15, 2025, and won by a ten round unanimous decision.