In March 1957, Okano graduated in psychology from the Faculty of Letters, and in early 1961 spent three months in West Germany to train as a football coach. Upon return he was appointed as a Japan national team assistant coach under manager Ken Naganuma, he also served as an interpreter for German coach Dettmar Cramer. In 1968 Summer Olympics, Japan won the bronze medals. In 2018, this team was selected Japan Football Hall of Fame. In 1970, he was promoted to the manager as successor Naganuma. He managed at 1970 Asian Games. However, at 1972 Summer Olympics qualification in 1971, following Japan's failure to qualify for 1972 Summer Olympics, Okano resined.