Widely regarded as the successor of Kohei Uchimura,[1] he won two gold medals at the 2020 Summer Olympics, in all-around and horizontal bar, as well as a silver in team.

[4][5] Hashimoto became a member of the Japan men's national gymnastics team in 2019, while he was still studying at Funabashi Municipal High School.

This would also include by default Hashimoto becoming the youngest Japanese gymnast to win Olympic gold on the all-around and horizontal bar events.

At the 2021 World Championships in Kitakyushu, Hashimoto was the top qualifier on the men's individual all-around and horizontal bar, but only earned two silver medals on those events.

At the 2022 All-Japan all-around championships in late April, Hashimoto successfully defended his title, leading in both qualification & final.

Hashimoto started the 2023 season with 2 gold and a silver at the 2023 DTB Pokal Stuttgart, where he won the Mixed Cup and horizontal bar events, while being the runner-up at Men's Team Challenge.

Later in April, he successfully defended the All-Japan All-Around Championships crown and became the 10th male gymnast to win the title 3 times.

In May, he also won the NHK Trophy for the third consecutive year, despite the falls on pommel horse and horizontal, as well as underperforming the floor exercise routine.

At the All-Japan Event Championships in June, Hashimoto was set to compete in floor, pommel horse and horizontal bar.

During the AA final, Hashimoto, who ranked 1st in qualification, clashed his head as he fell from the pommel horse and was forced to withdraw from the rest of the competition.

In men's team final, Hashimoto, together with Kenta Chiba, Kazuma Kaya, Kazuki Minami and Kaito Sugimoto won the gold for Japan for the 1st time since 2015.

Hashimoto represented Japan at the 2024 Summer Olympics in Paris, France alongside Tanigawa Wataru, Oka Shinnosuke, Kaya Kazuma, and Sugino Takaaki.