Yū Hamagashira is a retired Japanese voice actor and former singer who was active in the mid-2010s. She was born on February 25, 1998, in Fukui Prefecture, Japan. Hamagashira was affiliated with the talent agency Stardust Promotion. She also used the name Yuu Hamagashira for her professional work.

Hamagashira began her career in entertainment at a young age, winning a special judge award in an Avex modeling category in 2010. She later won first place in a Chinese speech competition in 2013. She debuted as a voice actor in 2014. That same year, she became a member of the voice actor unit Candy Voice, which was later renamed Aioke. Her career in the entertainment industry concluded on March 29, 2020, when she retired.

One of her early and most recognized voice roles is Kikako in the anime series Brynhildr in the Darkness, which aired in 2014. In this series, she voiced a minor antagonist magician. She also provided the voice for a student in the first episode of the same series.

In addition to Brynhildr in the Darkness, Hamagashira had several other anime voice roles, often for supporting or background characters. Her other credits from 2014 include the role of a couple woman and female students in Wolf Girl & Black Prince. In 2015, she played many minor roles in the anime Ultimate Otaku Teacher, voicing characters such as Ako, a clerk, customers, and various students across several episodes. She also appeared in the television anime adaptation of the series Life as a girl and a character named Pascal.

Beyond voice work for television anime, Hamagashira also performed on stage. In 2015, she was cast as Peko Pekoyama in the stage play adaptation of Super Danganronpa 2: Goodbye Despair Academy. She also played the role of Karuna Sen in a stage adaptation of ReLIFE.