Tetsuei Sumiya is a Japanese male voice actor born on November 13, 1993, in Ibaraki Prefecture, Japan. He is affiliated with the talent agency ARTSVISION. His journey to becoming a voice actor began in his childhood after discovering the profession in a book, which led him to pursue training at Nihon Kogakuin College and the Japan Narration Acting Institute.

Sumiya's career started in the late 2010s, with his earliest roles including minor characters in television anime such as Dr. STONE in 2019. He has since built a diverse portfolio of work across anime, video games, and drama CDs. Among his notable anime roles is Sirius Tenrōin in the 2021 series Fairy Ranmaru ~Anata no Kokoro Otasuke Shimasu~. In 2022, he voiced the character Zan Amaru in the anime adaptation of Lucifer and the Biscuit Hammer (Hoshi no Samidare). He is also part of the cast for the multimedia project Paradox Live, playing the role of Kantarō Misuji (credited as Sанshuji Kantarō).

Beyond these credits, Sumiya has secured main or recurring roles in several other projects. He is the voice of Aproo Link in the HIGH CARD anime series, appearing in both its first season in 2023 and second season in 2024. His work in video games includes the role of Hisaki Mitsuki in Readyyy! and Bail in Gran Saga. His involvement in drama CDs and character song projects is extensive, with credits in series such as Spy Hyakkaten, Kemuri, and Animal Therapia. Reflecting a recurring collaboration, he has co-hosted radio programs with fellow voice actor Kentarō Kumagai, including Ren'ai tte Nan nanda!?.

Sumiya is noted for his diverse talents and skills, which include singing, dancing, playing guitar and piano, and muscle training. A distinctive aspect of his profile is his proficiency in Chinese, specifically the Shanghai dialect.