This is a collection of reports sent by Admiral Yi Sun-shin to the government during the Japanese invasion of Korea, referred to as Imjin War. And the book’s reports are copied by an unknown person. It has the reports sent from the date of April 15, 1592 to April 20, 1594, a total of 68 reports. The contents of the reports are the political situation of Japan, news of victorious battles, achievements made by the commanders and the naval forces, and others. Additionally, it also has the articles written by Yi Hang-bok(1556~1618) and Park Seung-jong(1562~1623).