The purpose of this study is to overview the method and content of disaster information transmissions in Ancient Japanese. In order to deal with a disaster, a government starts with knowing the scale and situation of the damage in the disaster area. It will be unchanged in both modern and ancient. In the case, knowing how to transmit disaster information in ancient would be important in terms of understanding of disaster countermeasures by the ritsuryo state. The first chapter confirms the method of information transmission by statutes and three cases. The disaster information was transmitted promptly by 馳駅 and 逓送方式 in both cases of that the government reported to the province and that the province reported to the government. The second chapter examines the contents of information transmitted in the case of that a disaster happened in a province and considers the contents of information requested to be transmitted. As a result, this study pointed out that transmitting the damages of the people or their houses with numerical figures by the provinces was important to both the provinces and the government. It is presumed that the disaster relief system implemented by the ritsuryo state or the ideology for maintaining control of the people tabs on people by ritsuryo state was an assumption.