Judo Boy (紅三四郎, Kurenai Sanshirō, "Scarlet Sanshiro") is a Japanese anime television series created by Tatsuo Yoshida and directed by his brother, Ippei Kuri (birthnamed Toyoharu Yoshida).

The series aired on Fuji TV from April 2, 1969, to September 24, 1969, totaling 26 episodes.

[1][2] While originally based on a manga by Kuri and Yutaka Arai, published by Shueisha in 1961, the series was also followed by two manga adaptations, the first written by Yoshida and illustrted by Mamoru Uchiyama published in Shogakukan's Weekly Shōnen Sunday from July 28 to November 17, 1968,[3] and a four-chapters series written and illustrated by Yoshida in Shueisha's Weekly Shōnen Jump from May 22 to July 10, 1969.

[4] The series stars a teenage martial artist named Sanshiro (voiced by Ikuo Nishikawa), trained in the Kurenai School of Jiujitsu and centers around his search for his father's killer.

Kenji Utsumi as the Narrator Fuyumi ShiraishiHaruko KitahamaJunpei TakiguchiKaneta KimotsukiMasako IkedaMasashi AmenomoriRokuro NayaSeizo KatouTakeshi Aono