Mitsuki Saiga is a veteran Japanese voice actress and singer born on June 12, 1973, in Saitama Prefecture. She is affiliated with the talent agency Ken Production. From a young age, she aspired to be a voice actress and pursued this goal, later graduating from the Yoyogi Animation Gakuin.

Saiga is widely recognized for her distinctive, low, and resonant voice, which allows her to convincingly portray a wide range of characters. She is frequently cast in boyish or young male roles, a niche in which she is considered a leading figure, but also occasionally plays mature women. Her filmography is extensive, with prominent roles including Tsukasa in.hack//Sign, Jing in Jing: King of Bandits, Wolfram von Bielefeld in Kyo kara Maoh!, Sōji Okita in Peacemaker Kurogane, and Rossiu Adai in Gurren Lagann. In the 2010s and beyond, her notable roles have included Kuranosuke Koibuchi in Princess Jellyfish, Takuto Shindou in Inazuma Eleven GO, Opera in Welcome to Demon School! Iruma-kun, Yelena in Attack on Titan The Final Season, and Hayase and later Kahaku in To Your Eternity. In video games, she is known for voicing Tiz Arrior in Bravely Default and Mòrag in Xenoblade Chronicles 2.

For her work, Saiga has received several accolades. At the 2nd Seiyu Awards in 2008, she won the Best Supporting Actress Award for her performances in Moyasimon: Tales of Agriculture, Gurren Lagann, and Toward the Terra. Two years later, at the 4th Seiyu Awards, she was presented with the Overseas Fan Award, recognizing her international popularity for roles like Wolfram in Kyo kara Maoh! and Sōji Okita in Peacemaker Kurogane.

Beyond acting, Saiga is also a singer and has a band named Mitsuki Saiga feat. JUST, formed with musician Nishioka Kazuya. The band has released several albums and singles that have appeared on Oricon charts. For adult-oriented games and anime, she has used the alias Makoto Sato. Over her long career, she has frequently collaborated with a wide circle of fellow voice actors, with Shinichiro Miki, Takahiro Sakurai, and Katsuyuki Konishi being among those she has worked with most often.