Seishiro "Henry" Okazaki (岡崎 星史郎); January 28, 1890 – July 12, 1951) was a Japanese healer, martial artist, and founder of Danzan Ryu jujitsu.

Through hard training in the martial arts, Okazaki recovered completely and vowed to dedicate his life to propagating jujutsu and judo.

A synthesis of several older styles of jujutsu, Okazaki included in the system elements of his studies of Judo, Okinawan karate, Chinese kung-fu, Hawaiian Lua, Filipino knife fighting (escrima), boxing and wrestling,[3] as well as traditional Japanese restorative massage and healing techniques (Seifukujutsu).

Okazaki initially faced opposition within the Japanese-American community for teaching outsiders Japanese martial arts.

In addition to the martial disciplines, Okazaki studied health sciences and physical therapy, and ultimately gained a reputation as a healer of the sick and injured.