公元804年,日本僧人空海受派来到唐朝,回国后,作文记叙出使经过。本文以空海在福建上岸入唐的史事及其撰写的文书为考察对象,从而引发并解决了一二饶有趣味的中日交往史上的疑难问题。 In AD 804, the Japanese monk Konghai was sent to the Tang Dynasty. After returning to his hometown, his essay was written and made an introduction. This article takes the history and the writing instruments of the empty sea going to Fujian in Fujian as the object of investigation, which has triggered and solved the troublesome problems in the history of Sino-Japanese exchanges.