Abstract: In view of shortcomings such as poor reliability, high error rate existed in current leakage protection system of underground high-voltage power grid，a design scheme of leakage protection system of underground power grid based on ZigBee wireless sensor network was put forward. The system adopts CC2530 as core and uses improved RSSI location algorithm to locate fault position，which realizes remote fault location, and reduces error rate. The test results show that performance of the system is stable, and meets requirements of leakage protection of underground power grid.