He graduated from Okura Higher Commercial School in 1924.
Yoshinori Okage was a president of Nihon Sempaku Kogyo Kaisha (Japan Shipping Industrial Enterprise Company) and Nitto Shokuryo Kaisha (Foodstuff Company). He became managing director of Hoko Mining Company (1934). He held additional post of director of Chosen Kikai Kaisha (Korea Machinery Company) and engaged in operation of various coal mines in Korea.
Yoshinori Okagami served also as director of Tanaka Machinery Company, Fuji Kanko Kaisha (Tourist Industry Company) and Ohira Seito Kaisha (Sugar Refining Company).