Kaoru Kobayashi is a highly esteemed Japanese actor whose career spans over five decades, encompassing extensive work in live-action film and television alongside notable voice acting roles in animation. Born in Kyoto on September 4, 1951, Kobayashi began his acting career in the 1970s. He has received numerous accolades for his performances, including multiple Japan Academy Film Prizes and awards from the Yokohama Film Festival.

While Kobayashi is primarily known for his live-action roles, his voice acting work includes several significant animated projects. One of his earliest and most distinctive voice roles was as Saitō in the 1987 animated film Twilight of the Cockroaches, a unique live-action/animation hybrid that explores the coexistence of humans and cockroaches. He also provided his voice for the character Toshi-chan in the 2000 Studio Ghibli short film Ghiblies.

Kobayashi has developed a recurring collaboration with Studio Ghibli, contributing his voice to multiple films by the renowned animation house. He voiced the role of Jiko-bō, a monk, in Hayao Miyazaki's epic fantasy Princess Mononoke in 1997. He later took on the role of The King in Goro Miyazaki's Tales from Earthsea in 2006. Decades later, he returned for another Miyazaki film, providing the voice for the Old Pelican in the Academy Award-winning The Boy and the Heron in 2023.

Continuing his engagement with animation in the 2020s, Kobayashi is set to take on a leading voice role in the original animated film Hōsenka, scheduled for release in October 2025. He voices the main character, a yakuza named Minoru Akutsu, in his later years. This role was noted as a significant voice performance, with Kobayashi himself reflecting on the immersive and demanding nature of the recording sessions. His extensive and celebrated career in front of the camera is complemented by these distinctive contributions to animation, marking him as a versatile talent whose voice has become a part of some of Japan's most beloved animated works.