Yukiya Hayashi is a Japanese voice actor affiliated with Tokyo Actor's Consumer's Cooperative Society, also known as Haikyō. He began his career in 2019 as a member of Office PAC before moving to his current agency in 2025. He was a second-round winner of the Kimikoe audition. Hayashi was born on February 6th in Saitama Prefecture and stands 171 centimeters tall. His listed special skills include singing, playing the guitar, and computer programming, and his hobbies include playing music games.

Hayashi's anime roles include his performance as the renowned literary figure Ryūnosuke Akutagawa in the 2020 series Woodpecker Detective's Office. He later voiced the character Asuka Kurumaru in the 2024 anime adaptation The Stories of Girls Who Couldn't Be Magicians. His other anime credits include roles in Delicious in Dungeon as Dandan, Bye Bye, Earth as a member of the Bow Eye Tribe, The World Ends with You the Animation as a member of 777's bandmate Tenho, and minor roles in series such as Lupin the Third Part 6 and the Key animated series Kaginado.

In addition to anime, Hayashi has an extensive portfolio in voice-over work for foreign films and television series. He provides the Japanese voice for Theo in the series The Lord of the Rings: The Rings of Power. Other prominent dubbing roles include Miguel in Cobra Kai, Harry in Heartstopper, and Dash (contestant number 141) in Squid Game: The Challenge. He has also voiced characters in the films Insidious: The Red Door, Joe Bell, and Step Up: Year of the Dance.

Hayashi's work also extends to video games and audio productions. He has contributed voice work to the games Stranger of Paradise: Final Fantasy Origin, Final Fantasy XVI, and NEO: The World Ends with You. He has also performed in voice dramas, such as in the series Ouchi Shigoto Meito with WORK, and for audiobooks, including the fifth volume of the novel Kamisama no Goyōnin.