The invention discloses a laser monitoring system for circuit breaker body fault displacement. The laser monitoring system comprises a laser transmitting device, a laser reflecting sheet, a laser sensor receiver, a digital-to-analog conversion module and a background server. The laser transmitting device is installed on the bottom part of the basic frame of a circuit breaker facing a current transformer side. The laser sensor receiver is arranged on the circuit breaker internode flange of the circuit breaker facing the current transformer side. The laser reflecting sheet is fixed on the basic frame of the current transformer facing the circuit breaker side through a rotatable metal fixing arm. According to the system, every action of the circuit breaker in a transformer substation is used as an excitation signal, the measurement device uses laser measurement, and the change of relative displacement between the laser monitoring body arranged on the circuit breaker body and the basic frame is measured and the monitoring result is transmitted to the master control background, and the system alarms through the background when the change of displacement exceeds the allowed range so that accurate monitoring and timely alarm of the work can be realized.