Abstract: Aiming at the problems of limited coverage and imperfect function caused by the inflexible communication mode of the existing mine broadcast system, a design scheme of mine broadcast system integrating Ethernet, CAN bus and analog audio transmission is researched and designed, and the system architecture, hardware and software design and core technology of the system are described. The hardware of the system is composed of broadcast terminal and broadcast intercom speaker. The broadcast terminal uses Ethernet communication to realize network IP telephone and complete long-distance communication; broadcast intercom speaker through the CAN bus, combined with analog audio to achieve two-way intercom and streaming media online playback, with CAN relay function, can be unlimited cascaded, can be deployed where the optical fiber can not cover. The whole set of broadcasting system can realize full coverage of underground voice in coal mines, with the advantages of easy installation and low hardware cost, and provide strong support for daily safe production scheduling and disaster prevention and avoidance in coal mines.