There are two points in this treatise. The first point is to testify the existence of the "Asukakiyomibara-Ritsuryo" in between the Omi-Ryo and the Taiho-Ritsuryo in the history of codification in ancient Japan. The theory hitherto believed in has recognised its existence. But this theory has been denied recently by Mr. Nakada. Against this recent theory, the author maintains its existence by quoting proofs both positive and negative from old documents, such as the " Shokunihongi, " the " Koninkyaku-jo " etc. The second point is to find out the original text of the " Asukakiyomibara Ritsuryo ". The author asserts the possibility of reconstructing some articles of this code through the interpretation of the descriptions of the " Nihon-shoki "