At present, the same-tower multi-circuit and high-current-carrying wire technology is used to increase the transmission capacity of the line, and its induction level is an important basis for the protection of maintenance workers and equipment selection. This article establishes a line simulation model for a 500kV double-circuit transmission line on the same tower, and studies the influence of the length of the double-circuit line on the same tower, the protection angle of the lightning line, the line flow, the horizontal spacing of the conductors between the loops, and the induced electricity of the soil resistance. The information coefficient (MIC) analyzes the sensitivity of each factor. The results show that: the electrostatic voltage is affected by the conductor (MIC=0.735) and the protection angle (MIC=0.69); the electromagnetic voltage is related to the length of the common tower, the power flow and the conductor spacing; the length of the common tower (MIC=0.82) and the conductor spacing (MIC= 0.70) Obviously affect the magnitude of electrostatic current; electromagnetic current is highly correlated with tidal current and spacing; the influence of soil resistivity is negligible. The research results provide a technical reference for the maintenance of EHV transmission lines and the formulation of safety protection measures for operators.