Identifying the decisive influence factors of high voltage transmission lines on the electromagnetic scattering field of neighboring radio stations and suppressing the interference amplitude is the most effective way to solve the current transmission line passive interference problem. In order to study the decisive influencing factors of the scattering field of transmission lines in the shortwave frequency band, combined with electromagnetic scattering theory, a transmission line route-surface hybrid model is constructed. The RWG basis function and Galerkin are used to test the discrete induced current, and the scattered field is solved by the electric field integral equation. Through the correlation between the induced current of the transmission line and the scattering field, The influence of the main structural characteristics of the transmission line ground wire, line spacing, number of towers and tower height on the distribution of induced current is analyzed, and the influence factor of the electromagnetic scattering field of the transmission line is indirectly determined.The results show that the complex metal structure scatterer of the transmission tower is an important influence factor of the electromagnetic scattering field of the transmission line under electromagnetic wave.