Masuo Amada is a Japanese actor and voice actor born on January 20, 1958, in Hyogo Prefecture. He is affiliated with the theatre company Seinenza Theater Company, where he has built a career spanning both stage performances and voice work for animation and video games.

Amada's voice acting career is extensive, with credits dating back to the 1990s. He has portrayed a wide range of characters, often bringing to life imposing figures, villains, and authority roles. Some of his more prominent early roles include the hulking mercenary Pippin in the 1997 adaptation of Berserk and the massive snake Manda in the long-running series Naruto and Naruto Shippuden. He also voiced the character Crocus in One Piece and a Lancer Evolution driver in Initial D. His filmography includes minor roles in classic series like Trigun and Master Keaton.

In the 2000s, Amada continued to build a diverse portfolio. He provided the voice for the character Darius in Fullmetal Alchemist: Brotherhood and appeared in Mobile Suit Gundam: MS IGLOO. In the 2010s, he took on several prominent roles, including the father of the three titular girls, Sōjirō Marui, in the comedy series Mitsudomoe and its sequel Mitsudomoe Zōryōchū!. He was also the voice of Duran in the fantasy anime GATE. During this period, he voiced the character Gula in the magical girl series Glitter Force Doki Doki (DokiDoki! Precure). He also appeared in the long-running franchise The King of Minami in a live-action role as Shoichi Hirose.

In more recent years, Amada has remained active in the industry. He voiced the demon Nept in the action series The Idaten Deities Know Only Peace and took on the role of Dian Cecht in the third season of Is It Wrong to Try to Pick Up Girls in a Dungeon?. In the space opera franchise, he played Daeder in Space Battleship Yamato 2205: The New Voyage. He also voiced the villainous Braiking Boss in the crossover film Pandora to Akubi. His other roles from the user's list include Hozoin Inshun in the 1997 OVA Ninja Resurrection, Yamazaki Yoshiie in both Ninja Girl & Samurai Master 2nd and 3rd, and Colonel Ka Gae-Ru in Ghost in the Shell: Stand Alone Complex: Solid State Society.

Beyond animation, Amada is also known for his work in video games, most notably as the voice of Jecht, the father of the protagonist, in the critically acclaimed Final Fantasy X. He has also contributed to the field of voice-over (or "fukikae") for foreign productions, such as providing the Japanese voice for the character Zhang Fei in the Chinese television series Romance of the Three Kingdoms. His work in live-action tokusatsu series includes voicing the villain Salamandam in Kaizoku Sentai Gokaiker.