Abstract: In view of the problems of poor reliability of information transmission and low fusion degree of heterogeneous data for coal mine safety monitoring system, a multi-protocol fusion gateway for underground coal mine was designed. The gateway can be connected to sensors with different protocol types at the same time and transmit multi-source data to remote server in the form of Ethernet protocol data for information fusion. In the gateway, physical layer receives data information of the terminal through different protocols (RS232, RS485, CAN, ZigBee) transmission medium and interface. Protocol layer de-archive different data formats to obtain original data of the end user. System layer completes access of multiple types of devices through task management and communication scheduling. Application layer designs user function and calls the kernel space network layer protocol for data encapsulation to obtain the data in the Ethernet protocol format, the data can be transmitted to the upper node without processing, so as to complete conversion and transmission of multi-type protocol data to the Ethernet protocol data of the gateway. The test results show that the gateway can realize transparent transmission of RS232, RS485, CAN, ZigBee protocol data to Ethernet protocol data, and the transmission delay is concentrated within 15 ms, the packet loss of transmission data is extremely low, so the gateway has a strong communication reliability.