He was a son of ONAKATOMI no Sadanobu (大中臣定登) and was adopted as a son of ONAKATOMI no Kinnaga who was his uncle (the youngest brother of his father) and Junii saishu (Junior Second Rank, chief priest).
大中臣定登の子で、叔父（父の末弟）の従二位祭主大中臣公長の養子となった。