His diary that started at the age of around 11 and ran until his death has been handed down as an important historical material on the insei period (during the period of the government by the retired Emperor) in the reprint name of "Choshuki" (The Diary of MINAMOTO no Morotoki).
彼が11歳頃から没年までつけていた日記は、現在では『長秋記』として翻刻され院政期の重要な史料として伝わっている。