 He graduated from Tokyo Imperial University.He earned a Ph.D from Nagoya University in 1962.In 1937, Ōkita worked as an engineer with the Ministry of Posts.Later on he held numerous government positions, including chief of research for the Economic Stabilization Board in 1947, chief of the economic cooperation unit for the Economic Planning Agency in 1953 and later director general of their planning bureau in 1957, and then in 1963 the director general of the EPA development bureau.