Gianfranco Mastrorosa is a Venezuelan voice actor known for his work in anime, television series, and films, primarily in Spanish dubbing. He developed an early interest in the audiovisual world and began his career by creating fandubs on YouTube before pursuing professional training. He is a graduate of the Escuela Superior de Doblaje in Venezuela. Before fully dedicating himself to voice acting, Mastrorosa pursued a different academic path, earning a degree in Geophysical Engineering from the Universidad Simón Bolívar in Venezuela in early 2018. This background in engineering is noted for contributing to his detailed and disciplined approach to his craft. He currently resides in the United States, where he works as a freelance voice actor and voice-over artist, and has been involved in dubbing for major networks such as A&E, History Channel, and E! Entertainment.

In the realm of anime, Mastrorosa is recognized for his contributions to the popular series My Hero Academia. He provides the voice for multiple characters within the series, including Higari Maijima, also known as the hero Power Loader, and Tsunagu Hakamada, the hero Best Jeanist. Notably, he also voices the character Inasa Yoarashi, a powerful student from Shiketsu High School who plays a significant role in the series' Provisional Hero License Exam arc. His other anime credits include a role in the horror mystery series Higurashi: When They Cry - GOU, where he voiced Ken Sonozaki, in addition to providing extra voices for the show and for a My Hero Academia OVA. His work also extends to donghua, the term for Chinese animation, having voiced Han Wenqing in the film The King's Avatar: For the Glory.

Beyond animation, Mastrorosa's voice acting career spans a wide variety of genres. He has voiced characters in live-action television series, such as the character Dominic Consuelo in the Filipino drama Conexión del alma, and has contributed to reality shows, documentaries, and films. His work includes voicing characters in the long-running animated series South Park for its twenty-fifth season and starring as the title character in the animated series Tito Lizzardo.

Mastrorosa's professional achievements include being invited, alongside fellow Venezuelan voice actor Jonathan Castellanos, to have their own panel at the 2025 San Diego Comic-Con International. Their presentation focused on the evolution and practice of remote dubbing, a model that allows voice actors to work from anywhere in the world, a method that became prominent during the pandemic. This panel highlighted their role in promoting new ways of working within the industry and demonstrating how dubbing is no longer confined to a physical studio. Their participation at such a major event serves as a recognition of their passion and effort, and they have become examples for new generations interested in pursuing a career in voice acting, emphasizing that discipline and dedication are key to success in the field.