However, as for the factor of foundation of it, not only internal circumstances at the University of Tokyo previously noted, but also that Hirobumi ITO who almost completed a draft of the Constitution of the Empire of Japan at that time advised to Koki WATANABE (president), 'The study on the science of the nation should be immensely encouraged, and we extremely need to inform people of underlying principle and implementation of constitution widely.' were deeply related to.
しかし学会設立の要因に際しては、先述のような東京大学内部の事情のみならず、当時大日本帝国憲法草案をほぼ完成していた伊藤博文が渡辺洪基（総長）に対し「大（おおい）ニ国家学ノ研究ヲ振興シ、普（あまね）ク国民ヲシテ立憲ノ本義ト其運用トヲ知ラシムルコトガ極メテ必要デアル」と助言したこと大きく関わっている。