Okuma served as the Minister of the Treasury from October 25, 1873 to February 28, 1880, but he had effectively been the highest officer of the Ministry of Treasury since he assumed the post of senior assistant minister of the Ministry of Treasury upon the launch of the modern Ministry of Treasury on August 15, 1869, therefore he continued to be in charge of the Ministry of Treasury and the Japanese financial policy until he was dismissed as the councilor during a conference in the presence of the Emperor on October 11, 1881 (Political Change of 1881), however his resignation as the Minister of the Treasury was because an agreement to serve exclusively as a councilor was reached by 'Proposal to Separate Councilor and Minister' promoted by Hirobumi ITO (a successor Minister of the Treasury was Tsunetami SANO, Okuma's direct subordinate).
大隈の大蔵卿在任時期は1873年10月25日‐1880年2月28日であるが、実際には1869年8月15日（旧暦明治2年7月8日(旧暦)）に近代大蔵省創立とともに大蔵大輔に就任して以来事実上の大蔵省の最高責任者であり、大蔵卿退任も伊藤博文が進めた「参議・省卿分離案」によって参議専念の合意が成立したこと（後任大蔵卿佐野常民は大隈直系）によるもので、実際には1881年10月11日の御前会議による参議免官（明治14年の政変）まで大蔵省及び日本財政の責任者であった。