The present disclosure provides an automatic stop device and an automatic stop method that enable an autonomous-driving traveling object to automatically stop. Automatic stop device automatically stops a vehicle in response to urgent information requiring urgency. Automatic stop device includes: urgent information receiver configured to receive the urgent information; urgency determiner configured to determine a degree of urgency about the urgent information by choosing from a plurality of levels in accordance with the urgent information; surrounding information acquisition unit configured to acquire information about a situation surrounding the vehicle; and stop time determiner configured to determine a time taken to automatically stop the vehicle. The time is determined in accordance with the degree of the urgency and the information about the situation surrounding the vehicle. Automatic stop device further includes automatic stop unit configured to automatically stop the vehicle upon a lapse of the determined time.