He was the third son of MINAMOTO no Morotoki (a son of MINAMOTO no Toshifusa, who was Sadaijin (minister of the left), and the author of "Choshuki") who was Gon Chunagon (a provisional vice-councilor of state) and from Murakami-Genji (Minamoto clan).
村上源氏の権中納言源師時（左大臣源俊房の子、『長秋記』作者）の三男。