In order to improve the detection efficiency of zero value insulator of transmission line,the unmanned aerial vehicles (UAV) equipped with an electric field detection device can realize live detection without climbing the tower. Firstly,the 1:1 simulation model of 220 kV porcelain insulator string is established. Through Comsol finite element numerical simulation,the influence of string type,path jitter,UAV and electric field probe on the spatial electric field distribution of insulator string is analyzed. Then,the identification model and background detection system of zero value insulator are established. Finally,the laboratory and field measurements are carried out. The results show that when double insulator strings have zero value insulators at the same time,their spatial electric field distribution does not affect each other. The offset distance of straight line detection path should be less than 50 mm during UAV flight. The space electric field distribution of insulator string is not affected by UAV and electric field probe. Using the zero-value insulator detection algorithm proposed in this paper,the field detection of zero-value insulators is realized by the UAV equipped with an electric field detection device.