Osamu Hosoi is a Japanese voice actor and narrator affiliated with the talent management firm ARTSVISION. He was born on September 22, 1964, in Saitama Prefecture and has been active in the industry since his debut in 1992.

Hosoi has built a versatile career spanning animation, video games, and tokusatsu productions. In animation, he is widely recognized for his long-running role as Fumihiro, the level-headed member of the Akina Speed Stars, in the Initial D franchise, a part he has played from the original 1998 series through to its spiritual successor, MF Ghost, in 2023. His other notable anime roles include the stern Kurama, the chief of the Diclonius research facility, in Elfen Lied, and John Smith in R.O.D -THE TV-. He also provided the voice for the character Sawada in the 1997 cyberpunk original video animation Psycho Diver: Soul Siren.

Hosoi has also contributed to several works directed by Mamoru Kanbe. He voiced the mecha character Stealth Robo in the 2003 Sunrise anime Shutsugeki! Machine Robo Rescue. Later, in Kanbe's 2006 horror OVA series Demon Prince Enma, he took on the role of Naojirou Abashiri, a member of the demon-hunting team.

Beyond these roles, Hosoi has an extensive filmography in video games, particularly with the company Capcom. He is the established voice of the character Dan Hibiki from the Street Fighter series, a role he has voiced in numerous installments since the 1990s. His other prominent game credits include Jet Stingray in Mega Man X4 and various characters in the Tales series. In the realm of tokusatsu, he has provided voice work for several characters in the Super Sentai franchise, such as RR Rii in Gekisou Sentai Carranger and Magnet Ninja Jishakkumo in Ninpuu Sentai Hurricaneger. Hosoi is also known for his extensive work dubbing foreign films and television series, most notably as the voice of actor Don Cheadle's character, Rusty Ryan, in the Japanese-language releases of the Ocean's Eleven film series.