To provide a communication device capable of exchanging further "living information".

A weight W(t) of time information and weight W(p) of space information are calculated for received accident information. When the total weight W(t)×W(p) calculated by multiplying them is less than a destruction threshold (S140; NO), the received accident information is destroyed (S180). When the total weight W(t)×W(p) is the destruction threshold or more (S140: YES), the accident information is transmitted to other communication device 1 or infrastructure (S170). When the total weight W(t)×W(p) is a use threshold or more (S150: YES), predetermined processing using the received accident information is executed (S160). For example, processing for displaying the occurrence point, time or the like of a traffic accident on a display device or recalculating a route bypassing the generation point of the traffic accident is performed.