Abstract: A traffic safety assistance device that can communicate with a plurality of moving objects and holds moving object information and map information, the moving object information including position information of some of the moving objects. The traffic safety assistance device is configured as follows. When position information of a first moving object and information about a second moving object existing around the first moving object are input from a terminal mounted on the first moving object, the traffic safety assistance device stores, in addition to the input position information of the first moving object, position of the second moving object in association with the position information of the first moving object as the moving object information.