Iori Hayashi is a Japanese voice actor and stage actor born on December 30, 1981, in Kanagawa Prefecture, Japan. He has been active in the entertainment industry since 2001 and has a blood type of O. His professional affiliations include the agencies Group Impact and Gekidan Alter Ego. Known hobbies include reading and listening to music, and he lists karate as a personal skill.

Hayashi is perhaps best recognized for his role as the voice of the iconic duel monster spirit Elemental Hero Neos in the popular anime series Yu-Gi-Oh! GX. In this role, he provided the Japanese voice for the signature card of the protagonist, Jaden Yuki, with the character becoming a central symbol of Jaden's deck from the show's third season onward.

In the long-running sports anime The Prince of Tennis, Hayashi voiced Hiroshi Chinen, a regular and the tallest member of the Higa Middle School tennis team. Chinen is known for his intimidating height and his use of a martial arts-based technique called Shukuchihou. Hayashi also portrayed the character Sakataki Jin in the anime series Time Stranger Kyoko. Sakataki Jin is one of the bodyguards to the princess protagonist, Kyoko, and is a member of the Dragon Clan who harbors secret feelings for her.

Beyond these key roles, Hayashi has contributed to other anime projects. His additional voice work includes a role in the film Rurouni Kenshin: New Kyoto Arc, Part II. He has also performed in various stage musicals, including the role of Higashikata Masami in the first-generation Yamabuki cast of The Prince of Tennis stage musicals, known as TeniMyu. His other stage credits include Anne of Green Gables (as Gilbert), Musical Hunter x Hunter: The Nightmare of Zoldyck, and Musical Adventurers.