The invention belongs to the technical field of measurement of 
high pressure gas 
discharge electromagnetism, and discloses a measuring device and method of 
roughness coefficient of a high-
voltage conducting wire. The measuring device is characterized in that: a 
cylindrical electrode is horizontally placed on a bracket, and is electrically grounded; the to-be-tested high-
voltage conducting wire is horizontally fixed on support rods, and is coaxial with the 
cylindrical electrode; the probe of a direct-
current electric field measuring device is placed in a circular hole in the 
cylindrical electrode, and is parallel and level with the inner surface of the cylindrical 
electrode; the to-be-tested high-
voltage conducting wire is connected with the output end of a high-voltage 
direct current power supply, a synthesis 
electric field is formed between the inner surface of the cylindrical 
electrode and the to-be-tested high-voltage conducting wire, and 
ion current is generated; one end of a sample resistance is connected with a 
metal thin film, and the other end of the sample resistance is grounded; a 
voltmeter is connected with the two ends of the sample resistance in parallel; the output voltage of the high-voltage 
direct current power supply is adjusted, so as to obtain the synthesis 
electric field intensity at the cylindrical 
electrode, the 
ion current density and the synthesis 
electric field intensity of the surface of the be-tested high-voltage conducting wire; the 
roughness coefficient of the to-be-tested high-voltage conducting wire is obtained according to the Peek formula. According to the measuring device and method of 
roughness coefficient of the high-voltage conducting wire, accurate measurement of the roughness coefficient of the to-be-tested high-voltage conducting wire can be achieved.