Due to the influence of high intensity alternating magnetic field generated by transmission power lines, the conventional physical sign monitoring system cannot accurately identify the physical sign information of operators during live working, making it difficult to effectively guarantee their life safety. Aiming at the above problems, an anti-electromagnetic interference (EMI) monitoring system for live working signs is designed and implemented. Under the premise of not affecting the normal work of operators, the system monitors their physical signs, and realizes the real-time transmission of the physical signs of operators through 4G communication technology. At the same time, in order to make the monitoring equipment work normally in the high-intensity alternating electromagnetic field environment with live operation, a switchable multi-band pass filter is designed to achieve selective filtering of signals, so that it can meet the needs of communication and anti-electromagnetic interference. Mobile software can display real-time data curve, alarm, tips, information such as time, equipment electricity, and can process the obtained signs information, review the status of workers signs in advance, so that workers can timely stop operation before entering the sub-health state, to achieve the function of real-time monitoring, alarm information.