Abstract: For monitoring the work states of optical remote sensor in real time and automatically alarming when the work states are abnormal, the power characteristic analysis method based on command sets of optical remote sensor was developed. By sampling and iterating the relationship between power and various command sets, the dynamic threshold function based on command sets was summarized. And the threshold function was optimized, since some actual conditions must be considered such as surge, command delay and so on. And the optimized threshold function was applied to the power monitor and control system. The system adopted 20 Hz sample frequency to monitor the power of optical remote sensor in the heat cycle experiment, which would last 12.5 days. The command refresh cycle was 512 ms of the optical remote sensor. The results show the method can exactly monitor states of optical sensor and alarm when the states are abnormal. That puts power alarm method of optical remote sensor into practice and has great value to tester.