Power cable joint is the weak link of power system’s safe operation, it is important significance to real-time master the operating temperature of power cable joint for the safety of the power system. This paper adopts wireless technology to design the temperature monitoring system of power cable joint. Monitoring terminal collection temperature data located in each power cable joint collects the measured data in the cable branch box through the near distance micro-consumption electronic wireless technology to data concentrators located at the bottom of the cable branch box, then transmits to the monitoring center through CAN bus network. The system realizes the low cost and on-line reliable monitoring of power cable point temperature of the urban cable branch box.