Ryo Nishizawa is a Japanese voice actor born on June 18 from Kanagawa Prefecture, where he is affiliated with the agency AXL-ONE. He possesses a mid-low to low vocal range and holds qualifications including an English Proficiency Test Level 2, a regular driver's license, and a BSAC scuba diving certification. His personal interests include golf, karaoke, collecting palindromes, composing haiku, and photography and video shooting. He also cites skills in editing books, magazines, and web media, mnemonic rhyming, and illustration.

Nishizawa made his debut in the theatrical anime film The First Slam Dunk. His television anime roles include Yoshihiko Sakura in AI no Idenshi, Alfred in Undead Murder Farce, a detective in Dead Mount Death Play, a male character in Doraemon, and a villager in The Seven Deadly Sins: Four Knights of the Apocalypse. More recent credits include Masakado Mikado in Blue Exorcist: Yuki no Hate-hen and Blue Exorcist: Shuuen-hen, a customer in Ippon Seisoku, Tomás in The Alchemist Who Will Become the Strongest Someday?, and the BXTV President in Trillion Game. His work in web animation includes a role as Customer B in T・P BON.

In the field of video games, he has voiced Maringue in Monster Strike. Nishizawa has an extensive catalog of dubbing work for foreign films and series, with credits including Oliver in The Rookie: Feds, the jailer, lord, and grand vizier in The King, the Pharaoh, the Princess, and the principal/Haruen and a mysterious man in The Last Summoner. He has also contributed as a narrator for projects such as Clarksons Farm and NHK programs Beautiful Alps Grand Jorasse and Beautiful Alps Gran Paradiso. His work includes audiobooks, such as playing James in I've Been Told I Found True Love. Information regarding major recurring collaborations with specific directors or animation studios, as well as notable career achievements such as awards or nominations, is not available.