Saruta was born in Kawaguchi, Saitama, Japan. Saruta was active in extracurricular activities in his youth, but had a focus on gymnastics. He wanted to be an Olympic athlete for his country of Japan, but would not realize that goal. When he was 18, Saruta saw Norifumi “KID” Yamamoto on television and decided to begin training in mixed martial arts. He is married.
Saruta made his professional MMA debut on January 26, 2008 at Shooto: Back to Our Roots 7 against Kota Funaki. He would lose the bout by TKO. On August 9, 2009, Saruta got his first professional victory over Takahiro Kohori at Shooto: Gig Saitama 1 by first-round TKO. Between August 2011 and April 2013, Saruta had his first-ever winning streak. He won five consecutive bouts in Shooto with two submissions and a knockout during the run. During this run, he won the Shooto Infinity Bantamweight tournament, with a majority decision win over Masumi Tozawa. This would earn him a title shot versus Ryuichi Miki. Their first bout ended in a draw, and their second in a unanimous decision loss for Saruta. After early failed attempts at winning Shooto titles, Saruta moved to Tokyo and changed camps to begin training with Wajutsu Keishukai Hearts. After an up-and-down stretch that saw Saruta go 3-4-1, the Japanese fighter began another five-match unbeaten streak that would lead to a flyweight title shot against Ryuto Sawada. On October 15, 2017, Saruta defeated Sawada by knockout in the fourth round to capture the Shooto flyweight championship. Following that, he achieved a decision win over Kiyotaka Shimizu and defended his title against Itchaku Murata, winning by way of TKO.
ONE Championship
On December 7, 2018, Saruta made his ONE Championship debut against former strawweight champion, Alex Silva. He won by unanimous decision. The victory in his ONE Championship debut earned Saruta a title shot against Joshua Pacio. On January 19, 2019, Saruta edged out Pacio by split decision to win the ONE strawweight world championship. Yosuke Saruta would fight a rematch with Joshua Pacio at ONE: Roots of Honor. Saruta lost the bout, after being knocked out by a knee in the fourth round. At ONE Century, Saruta bounced back with a KO victory over the Pancrase strawweight champion Daichi Kitakata, stopping his opponent in the first minute of the second round.
