In order to study the influence of electromagnetic environment of ±500kV double-circuit transmission line on live working, and provide the theoretical and numerical simulation studies of safety protection of live working.This paper takes the Z101 line tower of ±500kV double-circuit transmission line as the research object, and establishs a three-dimensional model of the line tower with the mixed modeling techniques based on COMSOL and SoildWorks. Using COMSOL, study of simulation is carried out towards the electric field and potential distribution of Z101 line tower according to the six different topical live working positions. The results show that: the potential difference of NO.5 position is the maximum. The potential differences of all the other positions except No.4 and No.5 are similar; besides, the maximum electric field strength of human organs apears on the neck and limbs; and the electric field strength of human organs of No.5 position is the strongest, which generally exceeds the limit value of safety operation. Therefore, the worker should wear screen clothes and make other safety precaution efforts before live working in the double-circuit DC transmission line, and the results of this paper could provide the technical reference of other projects.