Yasuoka Ryōsuke was a feudal lord of the Tosa Domain and a samurai of the in the late Edo period. He was a bureaucrat in the first half of the Meiji era, Shirakawa prefectural ordinance, and Kumamoto prefecture ordinance. During the Boshin War, he captured and beheaded Kondō Isami. He was the great-grandfather of Masahiro Yasuoka, a Yomei scholar who wrote Yangmingism drafting sentences of the imperial rescript during World War II.