Kenzo Masaoka was a Japanese animator and voice actor, born on October 5, 1898, in Osaka, and passed away on November 23, 1988, in Tokyo. He is regarded as a pivotal figure in the early development of Japanese animation, known for pioneering techniques such as the use of cel animation and the incorporation of recorded sound into anime. His innovative work in special effects and filmmaking earned him the nickname the Japanese Méliès. He also worked under the pseudonym Donbei Masaoka.

In addition to his work as an animator and director, Masaoka contributed to the medium as a voice actor. His most notable and well-documented voice role is in his own 1939 short film, Benkei and Ushiwaka. In this film, which retells the legendary encounter between the warrior monk Benkei and the young Minamoto no Yoshitsune, Masaoka provided the voice for the character Benkei. His wife also voiced the character Ushiwaka for the production. This film was significant not only for his voice performance but also for its production technique, as Masaoka experimented with recording the dialogue before animating the footage, a method adopted from American animation studios that was uncommon in Japan at the time.

Information about other voice acting roles or recurring collaborations in that specific capacity is limited. Masaoka's primary and lasting legacy is as a foundational animator and director whose technical innovations and mentorship helped shape the Japanese animation industry. He trained influential animators such as Mitsuyo Seo and Yasuji Mori and was one of the founders of the studio that would eventually become Toei Animation.