Rintaro Negishi is a Japanese voice actor born on July 19, 2005, in Chiba Prefecture, Japan. He is affiliated with the talent agency Amuse Creative Studio. His height is 176cm and his blood type is O. His stated hobbies include taking walks, singing karaoke, and playing the drums, while his special skills include baseball, track and field, soccer, and hard tennis.

Negishi began his voice acting career with a role in the short anime project I.ADORE, produced by Evil Line Records. He plays the character Utsuro Amanogawa in this series. The I.ADORE project centers on idols who express political ideologies through song and dance, creating an "Idol Sengoku Jidai" or Idol Warring States Era. The short anime debuted in January 2026. No information is available regarding other major voice roles, recurring collaborations with specific directors or fellow cast members, or notable industry achievements beyond this initial casting.