Kentaro Nakajo is a Japanese manga artist and original creator born in Kochi Prefecture in 1938. He began his professional career as an assistant to Osamu Tezuka and Hisashi Sekiya before making his manga debut in 1956 with Robot Kyō Jidai, published in Akita Shoten’s Bōken’ō magazine. Over the course of his career, he has worked under several pen names, including Ken Nakajo, Ken Nakajō, and Tateo Nakajo.

Nakajo is best known for his long-running creative partnership with writer Ikki Kajiwara, a prominent figure in Japanese sports manga. Together, they produced a number of successful fighting series. Their most famous collaboration is Kick no Oni, a manga serialized in Shōnen King from August 1969 to February 1971. The story is a fictionalized account of the life of real-life kickboxer Tadashi Sawamura. This manga was adapted into a 26-episode anime television series produced by Toei Animation, which aired on Tokyo Broadcasting System from October 1970 to March 1971. Nakajo is credited as the illustrator for the manga, with Kajiwara as the writer.

The same creative duo also worked on other martial arts-themed projects. Their manga Karate Jigokuhen was adapted into the original video anime Shin Karate Jigokuhen: Chi no Mokushiroku and Shin Karate Jigokuhen: Kessen no Kado, both released in 1990. Nakajo is credited as a screenwriter on these anime adaptations, alongside Ikki Kajiwara and Hideo Nanbu.

Beyond his work with Kajiwara, Nakajo has created a substantial body of manga across various genres. His other notable credits include the manga adaptation of the classic kaiju series Ultra Q, as well as series such as Bodyguard Kiba, Kurenai no Challenger, and Shikakuai Janguru. His career spans several decades, beginning in the mid-1950s and continuing through the 1980s and beyond, marking him as a significant contributor to the martial arts and action genres in both manga and anime.