Setsuo Itō is a Japanese voice actor born on March 18, 1991, in Hokkaido, Japan. He is affiliated with the talent agency AIR AGENCY, having graduated from the Human Academy Sapporo school and the AIR AGENCY voice actor training school.

Itō made his debut as a voice actor in 2013 and took on his first leading role in 2016. That year, he was cast as the protagonist Shigeo "Mob" Kageyama in the television anime series Mob Psycho 100. Director Yuzuru Tachikawa chose Itō for the role, noting that his clean image and lack of leading role experience at that stage of his career aligned well with the character's developmental journey from inexperience to personal growth. Itō reprised this role for all subsequent seasons of the anime, including Mob Psycho 100 II and Mob Psycho 100 III, as well as for the special REIGEN: The Miraculous Unknown Psychic. For his performance as Mob, Itō received the Best New Actor Award at the 11th Seiyu Awards in 2017.

In addition to his signature role, Itō has portrayed a variety of other characters across different series. His early work included the role of Ryōhei Ameyama in the 2013 series Pupipō!. He played Kai Musashikai in Anime-Gataris and the role of Ōhashi in the series Africa no Salaryman. In 2024, he voiced the character Yanagisawa in the series T·P BON. His other roles include Purson Soi in Welcome to Demon School, Iruma-kun and Cress in The Brilliant Healer's New Life in the Shadows.

Beyond television animation, Itō has worked on numerous video games, including providing voices for multiple titles in the mobile game series Sōkyū no Sky Galleon, as well as Macross Delta Scramble. He has also appeared in stage productions, performing the role of Mob in stage adaptations of Mob Psycho 100.