Born in Tokyo, his best-known part has been Daisuke Jigen in Lupin the Third. He is the only cast member of Lupin the Third to have been in every Lupin anime (with the exception of "The Fuma Conspiracy" due to the budget). He was also the narrator of the tokusatsu television series Ryuusei Ningen Zone Uchuu Keiji Sharivan Kyojuu Tokusou Juspion & Kamen Rider BLACK the anime series Gaogaigar and the tokusatsu movie Godzilla vs. MechaGodzilla II, and the voices of Gori in Spectreman, BaraDarts in Chouriki Sentai Ohranger, VRV Master in Gekisou Sentai Carranger, and Dekius in Seijuu Sentai Gingaman and Violence Jack in the second Violence Jack OVA, "Hell City." In the tokusatsu series Choujin Barom-1, he played Detective Kido, a relative of one of the main protagonists. Kobayashi has also voiced Watari from Death Note and Kouga Danjo in Basilisk: The Kouga Ninja Scrolls.