The purposes of this extremely important envoy of Taiho era were to restore the diplomatic relations with Tang which had been precarious since the Battle of Hakusukinoe, to proclaim to Tang the establishment of the full-scale capital and Ritsuryo system in Japan as a result of the reform since the time of Emperor Tenmu, as well as the foundation of the title of the emperor and the name of the country as 'Nihon' (Japan).
この大宝度の遣使の目的は、白村江の戦い以来冷却していた唐との交流を回復するとともに、天武天皇以来の改革で日本に本格的首都および律令体制が完成したこと、天皇号および「日本」の国号が成立したことを唐に対して宣言することなどを目的とする、非常に重要な使節であった。