Shun Takagi is a Japanese actor and voice actor, born on March 17, 1981, in Ishikawa Prefecture, though he spent his earliest years in Chicago, United States. He is a graduate of the Yoyogi Animation Academy. Takagi began his career in theatre, joining the troupe Alter Ego and later becoming a freelancer in 2010. In July 2005, he formed the popular performance unit SMILY☆SPIKY with fellow actor and voice actor Mamoru Miyano. After many years as a freelancer, he joined the talent agency Dolce Star in 2025.

Takagi is widely recognized for his voice roles in anime. He played the title character, Sunred, in the comedy series Tentai Senshi Sunred and its second season, a role that served as his first big break as a lead voice actor. Other significant anime roles include Noda in Angel Beats!, Seishirō Nagatomo in Blue Exorcist, Tomoya Seo in the Assassination Classroom series, Ganji Nishimoto in School Rumble, and Tetsuya Kusakabe in Reborn!. He has also contributed voices to long-running series such as One Piece and The Prince of Tennis. Beyond anime, his voice work includes the Japanese dub of Jason Brody in the video game Far Cry 3.

Takagi has a history of recurring collaborations with director Seiji Kishi, having worked under his direction on series such as Tentai Senshi Sunred, Angel Beats!, and Assassination Classroom. His partnership with Mamoru Miyano is a central feature of his career, with the two collaborating on music as SMILY☆SPIKY, releasing albums and singles. The duo's name reflects their aim to express the full range of emotions in their stage performances.

In addition to his voice work, Takagi maintains an active stage career, a foundation of his professional life. He has appeared in numerous stage productions, including the musical adaptation of The Prince of Tennis and the stage play Persona 5 the Stage. He also produces and performs in his own series of solo stage shows called Oreiro. His achievements are marked by a respected reputation for his versatility and consistent presence across both anime and live theater in Japan.