Masahiro Nonaka is a Japanese voice actor and narrator, born on October 15, 1968, in Hiroshima Prefecture, Japan. He began his career in the 1990s and was formerly affiliated with agencies such as Osaka TV Talent Bureau and Vozator, later working as a freelancer. His career is distinguished by a long-standing and prominent association with the game developer SNK.

Nonaka is most recognized for his role as Kyo Kusanagi, the protagonist of the long-running fighting game series The King of Fighters. He first voiced the character in The King of Fighters '94 and continued in the role for numerous sequels, including The King of Fighters '95, '96, '97, and many others through to The King of Fighters XIII. His portrayal extended to various spin-offs and crossovers, such as the Capcom vs. SNK series, SNK vs. Capcom: SVC Chaos, and NeoGeo Battle Coliseum. He also voiced Kyo in the 2005 anime series The King of Fighters: Another Day. His performance as Kyo became so iconic that he also voiced the character's clones, Kyo-1 and Kyo-2, in The King of Fighters '99. Another significant role for SNK was Basara (also known as Basara Kubikiri) in the Samurai Shodown series, starting with Samurai Shodown III in 1995.

Throughout his career, Nonaka has demonstrated a recurring collaboration with SNK, contributing his voice to numerous projects across various media. Beyond video games, he was a participant in live Neo Geo DJ Station concerts and appeared on the Japanese radio show Game Dra Night. As the voice of Kyo Kusanagi, he also became a member of the character image band, Band of Fighters, and contributed to several drama CDs and vocal albums related to The King of Fighters series, including The King of Fighters '96 Arranged Soundtrack and Neo Geo Guys Vocal Collection.

In addition to his voice acting for characters, Nonaka has built a substantial career as a narrator. His work in this field includes providing narration for television programs and commercials for a wide range of clients, from regional businesses like Hiroshima Toyo Carp and Chugoku Electric Power to national brands like ROHTO Pharmaceutical. From 2002 to 2006, he also served as the stadium DJ for the J-League soccer team Kyoto Sanga FC. His tenure as the voice of Kyo Kusanagi concluded with The King of Fighters XIII, as the character was recast for subsequent installments starting with The King of Fighters XIV.