The invention relates to a train collision prevention warning system. A train information collection module is used for collecting train status information, and the train status information comprises a train running line, a train location, a train speed, a safety level and the like; a wireless communication module is used for wirelessly broadcasting the train status information and wirelessly receiving the train status information broadcast by other trains; and a CPU (central processing unit) control processing module is used for receiving and processing the train status information of the train and other trains collected by the train information collection module and transmitted by the wireless communication module. The current train status information of the train can be broadcast wirelessly to other trains via the wireless communication module, the train status information wirelessly broadcast by other trains can be received by the wireless communication module, the running safety distance and speed can be judged by the CPU control processing module according to relationships between the train and other trains, and pre-warning signals can be sent to drivers and automatic train operation systems. The system has a simple and reliable structure and can be installed conveniently, the train drivers can promptly know running statuses of approaching trains, and the train running safety can be improved effectively.