They were famous as representative works of Tenpyo sculpture but the details of their construction and original names are unknown (The name 'Nikko and Gakko Bosatsu' were used later on and they were originally Bosatsu, attendants of Yakushinyorai (Bhaisajyaguru, Buddha able to cure all ills)).
天平彫刻の代表作として著名だが、造像の経緯等は定かでなく、本来の像名も不明である（「日光・月光菩薩」という名称は後世に付けられたもので、本来は、薬師如来の脇侍となる菩薩）。