Hideo Aihara is a Japanese film and television producer, director, and screenwriter known primarily for his work in live-action television and as a producer of anime. He was born in Tokyo, Japan, in 1954. Aihara began making independent films while still in high school, and in 1973, one of his directorial works won first prize in a special category at the first "Film Festival Recording Japan," also receiving the Yomiuri Shimbun Award. The film earned praise from director Nagisa Oshima and was screened in Europe. After graduating from university, Aihara entered the television industry, where he directed numerous television documentaries and dramas.

In 1991, Aihara founded the production company Planet, which was later renamed Planet Entertainment, and he serves as its representative director. In 1998, a drama he produced received the Galaxy Prize, a prestigious award for Japanese broadcasting. His production work spans multiple genres, including television programs, films, anime, and international co-productions.

In the field of anime, Aihara is best known as an original creator and producer for the science fiction series The Galaxy Railways. The anime, which aired in 2003 and 2004, is a spin-off of Leiji Matsumoto's famous Galaxy Express 999 series. Aihara is credited alongside the legendary manga artist Leiji Matsumoto as an original creator and producer for the project. His role as an executive producer on the anime is also documented. The series was produced by his company, Planet. Aihara's contribution to the project represents a collaboration between his production company and Matsumoto's established creative universe. Beyond this notable anime credit, Aihara continues his activities as a producer and film director, though his output as a director in later years has been less frequent.