Reiji Kawashima is a Japanese voice actor born on November 30, 1995, in Aichi Prefecture. He was inspired to pursue a career in voice acting by the video game Final Fantasy X. He is a graduate of the Nagoya School of Music and Dance and the AIR AGENCY voice actor training school.

Kawashima began his professional career in 2017, taking on minor roles in anime series. His first leading role and major breakthrough came in 2021 when he was cast as the protagonist Fushi in the anime adaptation of To Your Eternity. The same year, he also voiced the dual roles of Patrick and Ricky in the series Shadows House. Later in 2021, he transitioned from his initial agency, Air Agency, to Aoni Production, where he continues to be affiliated.

Since his debut, Kawashima has built a diverse filmography with a significant number of main and supporting roles. These include Finn Ames in Mashle: Magic and Muscles, Jonas Anders in Sugar Apple Fairy Tale, Luciel in The Great Cleric, Blade in Classroom for Heroes, and Taiyō Asano in Mission: Yozakura Family. He also voices Suō Yobitsugi across multiple entries in the Cardfight!! Vanguard DivineZ anime series, including DivineZ and Divinez Deluxe-hen. Other roles include Isaac Sean in Gorilla no Kami Kara Kago Sareta Reijō wa Ōritsu Kishidan de Kawaigareru and Ren Ashiya in Shūkan Ranobe Anime. His work also extends to video games, with notable appearances in titles such as Monster Strike, Touken Ranbu, and Final Fantasy XV.

In recognition of his rapid ascent and promising talent in the industry, Kawashima was awarded the Best New Actor Award at the 16th Seiyu Awards in 2022.