The invention discloses a traffic flow dynamic guiding method based on a region block. A vehicle-mounted terminal establishes communication connection with a cloud server; the vehicle-mounted terminalconducts data acquisition and uploads the collected data to the cloud server; the feedback of the cloud server is received by the vehicle-mounted terminal; the feedback includes the probability thatan accident of a current car occurs within the current road section setting range; after the vehicle-mounted terminal receives the probability that the accident of the current car occurs within the current road section setting range, the probability is sent to a driver through human-computer interaction; in the establishment of the region block relationship, the current vehicle-mounted terminal receives communication addresses, sent by the cloud server, of the surrounding vehicle-mounted terminals within the setting range, and the current vehicle-mounted terminal establishes the connection relationship with the surrounding vehicle-mounted terminals through the communication addresses; after the region block relationship is established, running is conducted; the region block relationship isupdated; the region block relationship is used for conducting traffic flow guiding on vehicle accident information; the region block relationship is used for conducting traffic flow guiding on official vehicles. The method fills in the gaps of the vehicle traffic flow dynamic guiding in the traffic field.