The disaster information system according to the invention includes a disaster noticing server and a disaster reporting terminal. The disaster noticing server calculates the expected time of arrival at which the natural disaster will arrive at the current location of the disaster reporting terminal, and transmits the calculated expected time of arrival to the disaster reporting terminal. The disaster reporting terminal, when it receives the expected time of arrival from the disaster noticing server, acquires the current time measured at the disaster reporting terminal, and calculates the time remaining until the natural disaster will arrive at the disaster reporting terminal from the expected time of arrival and the current time.