The invention discloses a bidirectional broadcast type inter-vehicle communication system and method. The system mainly comprises a wireless transceiver and an information processing device, the wireless transceiver comprises an antenna, a duplexer, a transmitter, a code modulator and a receiver, and the information processing device comprises a system controller, a information parsing processor, a broadcast information preprocessor, a ranging processor, a vehicular system interface, a sensor interface, a display and position interface and an information processing center. The method includes the technical processes of broadcasting vehicular information outwards, receiving broadcast information of adjacent vehicles in real time, measuring relative distance of front and back vehicles within communication distance, warning the surrounding vehicles within a certain distance range, transmitting warning information to subsequent vehicles and receiving passed vehicle broadcast information in real time. By the system and method, functions of collision-avoidance warning, traffic information rebroadcasting, traffic intersection information statistics and the like are realized effectively, and traffic accident occurrence rate is lowered.