Gustavo Martinez is a Brazilian voice actor, director, and actor based in São Paulo, Campinas, and Rio de Janeiro. His body of work encompasses dubbing for a wide range of productions, including live-action films and television series, as well as Western and Japanese animation.

In the realm of anime, Martinez has lent his voice to a variety of characters across numerous series. His notable roles in anime include voicing Hans Humpty in Rokka: Heroes of the Six Flowers, Lord El-Melloi II in Fate/Apocrypha, Julius Belkisk Harwey in Fate/Extra Last Encore, and Ukyo Ibuki in Beyblade Burst. He also provided voices for characters in series such as Baki the Grappler, Devilman Crybaby, and Yashahime: Princess Half-Demon. Beyond these, his anime dubbing credits include parts in Violet Evergarden, ID-0, Kuromukuro, and Yamada-kun and the Seven Witches.

In addition to his anime work, Martinez is active in dubbing Western animation. He voices Drácula in Hotel Transylvania: The Series, J.P. Mercer in O Mundo de Greg, and has contributed additional voices for popular shows like Rick & Morty and Castlevania.

A specific and credited role for Martinez is voicing Ava's father in the Brazilian Portuguese dub of the Pokémon animated mini-series, Pokémon: Path to the Peak. His work in this series adds to a broader portfolio of dubbing for live-action projects, where he has voiced characters in productions such as La Casa de Papel, The Marvelous Mrs. Maisel, and the role of Gordon Ramsay in several of the chef's reality television programs.