Cynthia Martinez is an American voice actress known for her extensive work in English-language dubs of anime series and films. Born on September 15, 1975, in Houston, Texas, she began her career in the mid-1990s and has been primarily associated with ADV Films and its successor companies, Seraphim Digital and Sentai Filmworks. In addition to her voice acting work, Martinez is also a singer and fronts the Latin band Sintema.

Martinez's entry into voice acting was distinctive, as her very first role was the lead character Lina Inverse in the English dubs of the Slayers movies and original video animations (OVAs). This debut quickly established her in the industry. She is also recognized for her long-running portrayal of Illyasviel von Einzbern across multiple installments of the Fate/kaleid liner Prisma Illya series. Another significant lead role came early in her career as Sora Naegino in Kaleido Star.

Her filmography includes a wide variety of characters in prominent anime series. She voiced the role of Mikako Nagamine in Makoto Shinkai's acclaimed film Voices of a Distant Star and Excel Kobayashi in the surreal comedy Excel Saga. Martinez has also provided voices for Kanna in Air, Mayu in Elfen Lied, Hermes in Kino's Journey, Hikari in This Ugly Yet Beautiful World, and Poemi Watanabe in Puni Puni Poemy. In the 2010s, her credits continued to expand with roles such as Tami Nishimikado in Hanayamata, Lily Bell in Bodacious Space Pirates, and Momoka Oginome in Cross Ange.

Throughout her career, Martinez has been a staple of the Texas-based voice acting community, frequently working alongside a consistent pool of directors and fellow actors associated with studios like ADV Films and Sentai Filmworks. Her contributions to the industry have been recognized with guest of honor invitations at various anime conventions across the United States, including Ani-Jam in 2013 and Ohayocon in 2015.