Abstract: Unmanned aerial vehicles (UAVs) are increasingly widely used in the inspection of substations. Due to the large number of substation equipment and dense layout, strong electromagnetic environment may damage UAVs. Defining the safe distance between UAVs and electrified body is the key problem to be solved. For this reason, firstly, the simulated discharge test of UAV motor suspension and conductor is carried out, and the 3D simulation model of real UAV and equipment in the strong electric field area of 500 kV station is established. The electric field distribution characteristics near the UAV are calculated and analyzed to study and analyze the safe operation distance. The results show that there is interaction between the UAV and the conductor corona discharge. The critical corona field strength affected by the UAV is 300 kV/m, and the distortion electric field value of the UAV is 2~3 times the original value. The operation safety distance under the electric field control condition is obtained. The minimum operation safety distances for UAV to inspection 500 kV pipe busbar and 500 kV side bushing of main transformer are 2.2 m and 2.1 m, respectively, which provides technical basis for the safe operation of the UAV inspection in the substation.