Masato Niwa is a Japanese voice actor known for his work in anime, video games, and Japanese dubbing for foreign films and television series. Born on October 18 in Aichi Prefecture, Japan, he is affiliated with the talent agency B-Box. Niwa began his voice acting career in the 2010s, taking on smaller roles such as crowd members and students in television anime before gradually expanding his portfolio.

His body of work includes a wide range of supporting and guest roles in prominent anime series. Among his television credits are appearances in Banana Fish, Vinland Saga, Jujutsu Kaisen, Spy x Family, and The Apothecary Diaries. In the theatrical animation field, he has contributed to films including Weathering With You and Evangelion: 3.0+1.0 Thrice Upon a Time. Niwa has also provided voices for video games such as Monster Strike.

Niwa is highly active in the field of dubbing, lending his voice to Japanese-language versions of major international films. These include Black Widow, Indiana Jones and the Dial of Destiny, Mad Max: Furiosa, and Jurassic World. He is also a performer in stage productions and has made appearances on television shows.

In a notable role, Masato Niwa has been cast as the character Mukumuku in the upcoming anime series Suikoden: The Anime, an adaptation of the Konami video game Suikoden II. This production is scheduled to premiere in October 2026.