He graduated from Kobe Higher Commercial School (later Kobe University) in 1909 and worked at Sakai Commercial in Kobe. He opened Idemitsu Shokai, a business selling oil, in Moji, Fukuoka in 1911 with the support of HIDA Jutaro, a wealthy investor from Awaji Island. He became a member of the House of Peers in 1937. He reorganized and established his company as Idemitsu Kosan to import and sell machinery and oil in 1940. After the war, he proceeded to build large tankers and refineries and established an oil company that imports crude oil, refines it, and sells the results. He collected art and established the Idemitsu Museum of Arts.