Sōnosuke Hattori is a Japanese voice actor born on December 17 in Gunma Prefecture, Japan. He is affiliated with the talent management firm Aoni Production. A graduate of the Aoni Juku Tokyo School's 16th term, he made his debut as a voice actor in 2015. Hattori's inspiration to pursue a career in voice acting came from watching the anime series Clannad during a period of studying for university entrance exams.

Hattori has built a career through a wide variety of roles in anime, video games, and other media. In anime, his early work included numerous minor and supporting characters in long-running and popular series such as Dragon Ball Super and One Piece. He has since taken on more prominent, recurring roles, including Mikawa Inuhiko in the Free! -Dive to the Future- television series and its subsequent compilation films. Other notable anime roles include Yūma Arima and Hajime Hazuki in Tokyo Ghoul:re, and Shigeo Yumita in The Caligula Effect. In the 2019 animated series Dino Girl Gauko, he provided the voice for the character Toshio.

Beyond anime, Hattori has an extensive portfolio in other areas of voice work. He has voiced characters in numerous video games, such as Junnosuke Sanada in Readyyy!, Ikkyu Fujikura in Fragment's Note Plus, and Chitose Amagaku in Ensemble Stars!!. He is also highly active in voice comics, lending his voice to characters in a vast number of series across various genres, including The Stories of Girls Who Couldn't Be Magicians and The Fragrant Flower Blooms with Dignity. His work in drama CDs includes roles in projects like Clock over ORQUESTA.

While a specific, consistent pattern of recurring collaborations with a single director or fellow actor is not prominently documented, Hattori's work places him within the broader Aoni Production talent pool. He has taken on roles in media mix projects that involve music and character songs, contributing to releases for games like Readyyy! and the Clock over ORQUESTA franchise. In addition to his performance work, Hattori has also participated in television programs and radio shows, demonstrating his versatility as a media personality. His personal interests include reading, playing football, and riding motorcycles.