For the transmission towers located at a high-elevation and open area, the significant vibration amplitude caused by the strong wind force will often be found on the affiliated high-voltage cables. Accordingly, the elaborated seismic analysis undertaken on them should be based on the consideration of the regional wind effects. In his research, 3-D beam elements and efficient cable elements will be used for modeling the tower bodies and transmission lines respectively so as to seize differences of deformed and stressed conditions among structural members for the transmission towers going through various topographies. Furthermore, to enhance the reliability and value in practice for the analytical outcome, an effective spatial soil-structure interaction model and an effective parameter called “failure index” will be utilized in the analyses. It is shown in the results that the dynamic responses of the transmission towers subjected to the heavy earthquake would be affected significantly by either the cable mass or transverse wind drag acting on the cables.