Yū Miyazaki is a Japanese voice actor born on October 7, 1991, in Kanagawa Prefecture. He became interested in pursuing voice acting during his college years after recalling a narration from a Central Japan Railway Company commercial he had heard as a child. With no prior acting experience, he prepared by writing and performing a solo stage show before entering a training school. He graduated from the Haikyo Voice Actors Studio in 2014 and joined the Tokyo Actor's Consumer's Cooperative Society in 2015.

His voice acting debut came in 2016 with a small role as an English-speaking combatant in the anime Matoi the Sacred Slayer. His early anime roles include Louis Blackwell in Little Witch Academia in 2017. He gained wider recognition with his first regular role as Kiel in the 2018 anime adaptation of 100 Sleeping Princes and the Kingdom of Dreams. In 2020, he was cast as Sachirō Hirugami in the popular sports series Haikyu!! To The Top.

Miyazaki has portrayed a range of characters across various genres. In historical drama, he voiced Taira no Shigehira in the 2021 series The Heike Story. In the fantasy romance genre, he played Quartz in I'm the Villainess, So I'm Taming the Final Boss in 2022. He has also appeared in the long-running sports franchise as Milky Milman in The Prince of Tennis II: U-17 World Cup, and in science fiction as Civet Anhern in Mobile Suit Gundam Hathaway. His other notable roles include Notrei in Star Twinkle Precure, Tsubaki in the Star Wars: Visions short Akakiri, and Ren Kochi in the Kakegurui Twin original net animation. In 2024, he voiced the male lead Itsuomi Nagi in the romance anime A Sign of Affection.

Beyond anime, Miyazaki has an active career in video games and dubbing. His game roles include Vergil in Angelique Luminarise and Casiel in Genjū Keiyaku Cryptract. For international live-action dubbing, he is known as the Japanese voice for actor Nam Joo-hyuk in series such as Start-Up and Twenty-Five Twenty-One, and he voiced Jayce in the animated series Arcane. Among his special skills are video production and video editing.

On October 2, 2023, Miyazaki announced his marriage to fellow voice actress Atsumi Tanezaki. The two had previously worked together on several projects, including Mobile Suit Gundam Hathaway and The Ancient Magus Bride.