Abstract: When the thyristor acts as a pulse power switch， the power loss can easily accumulate heat for the junction region of the thyristor in a short time， and the temperature of the junction may rise instantly and significantly， which poses certain risks on the safe operation of the device. Therefore， a quick and precise acquisition of the temperature of the pulse power switch is of vital importance， and an alarm needs to be automatically triggered when the temperature is over the security limit. In this paper， a temperature sensor， AD590， is used to collect the temperature signal， and an embedded system based on ARM is used to monitor and upload the temperature state of the pulse power switch in real time. Finally， the validity of the designed system is verified with both theoretic analysis and experimental results.