These years, galloping of bundle conductors has severely threatened the safety of overhead transmission lines and caused enormous losses of economy. So it is noted that the studies on development of effective anti-galloping devices have a great significance for resisting the galloping disaster of power system and for improving the safe and stable operation of the grids. In this paper, a new combined anti-galloping device based on the principles of energy dissipation, restraining the torsion and detuning was developed for ultra-high voltage (UHV below) overhead transmission lines. To perform such analysis, the combined anti-galloping design method was presented and the new device applicable was developed on the rotation-free spacer damper. Then the arrangement of this new anti-galloping device was detailed and the efficiency assessment was carried out for verifying its galloping deterrence effect. Finally, the elastic and damping tests, the high voltage tests as well as the fatigue tests were realized to prove that the device designed satisfies the necessary requirements of overhead transmission lines.