The hand-copied book The kenpō zyunanazyō (The Seventeen-Article Constitution)(《宪法十七条》) (National treasure-the Iwasaki Version) in the middle age of Heian was the oldest copy in the same kind of literatures, and there has been the Script type of Japanese Kanji, which retained the most ancient On'yomi (Sino-Japanese reading) and Kun'yomi (native reading) of the same kind. By using Syogakukan Version Nihonsyoki (《日本书纪》), Iwanami Version Nihonsyoki(《日本书纪》) and Iwanami Version The kenpō zyunanazyō (The Seventeen-Article Constitution)(《宪法十七条》) as evidences, and by using Kadokawa Version Sinzigen(《新字源》) and Taisyukan Version Sinkangolin (《新汉语林》) as reference coordinate, the research on the Japanese Kanji On'yomi (Sino-Japanese reading) and Kun'yomi (native reading) in the second article of The Kenpō Zyunanazyō (The Seventeen-Article Constitution)(《宪法十七条》) could identify the inheritance of Japanese Kanji On'yomi (Sino-Japanese reading) and Kun'yomi (native reading) from the previous generations, determine the source of Japanese Kanji On'yomi (Sino-Japanese reading) and Kun'yomi (native reading) . The results of this study will be reflected in the Japanese collection of Chinese characters in Tang Dynasty (《日藏唐代汉字钞本字形表》)(from the fourth to the ninth) , the base of Japanese Kanji On'yomi (Sino-Japanese reading) and Kun'yomi (native reading) and Japanese base index.