Abstract: Long span transmission bundle lines will more easily suffer galloping phenomenon than a single wire. Based on space-curved-beam theory, the finite element model based on 6-DOF node is built to simulate a transmission line. The spacers are assumed as a rigid body，and the finite element model of 4-bundle conductors is established according to the displacement compatibility conditions. The static finite element equation is built through the virtual work principle and solved by the Newton-Raphson iterative method. The results of examples show that the curved beam model of a transmission line is accurate to calculate the translational displacement. Considering the coupling of the translational and torsional deformation, torsion angle calculations are more precise, and the bending stiffness of the transmission line will also affect the torsional angle. The results for the parameter analysis of bundle conductors show that sags, split spacings, spacers, and boundary conditions have more great influence on the torsional stiffness, whileas the number of spacers cannot significantly increase conductor torsional stiffness.