Abstract: A mine-used real-time video transmission system was designed to solve problems of low video definition, unstable transmission rate and poor compatibility in existing underground video transmission system. The system uses 960 nm infrared laser as auxiliary light source, and uses MCCD image sensor to collect video signals, which improves video definition in low light intensity or dark environment. The collected PAL analog video signal is converted into YUV digital signal through video decoding module TVP5150, then the digital signal is compressed and encoded by H.264 through multi format codec, and UDP packet header is added for RTP encapsulation, which improves timeliness of video data transmission. The data is streamed through Live555 streaming media server, RTSP video streaming is encapsulated with ONVIF standard, and real-time video streaming data transmission is realized through Socket network programming, which improves system compatibility and transmission rate stability. The test results show that the system has video transmission rate of 2.190 Mbit/s and packet loss rate of about 1.256%, which meets real-time video transmission requirements.