Vibration control of transmission tower-lines system subjected to spatially varying ground motions is studied. Three-dimensional finite element calculation model of transmission tower-line system considering the geometrical nonlinearity of transmission line is established. Multi-support seismic time histories are generated according to code for design of seismic of electrical installations. Tuned mass damper consists of mass, spring element and damping element, and the control parameters is optimized. Using nonlinearity time history analysis method, the effects of vibration control of power transmission tower-line system under multi-support seismic excitations are investigated. The results show that the damping effect of tuned mass damper is significant, which could effectively reduce the seismic response of transmission tower. There is a tiny influence on the damping effect of transmission tower only considering wave passage effect and multi-support excitation, and the damping effect of multi-support excitations is better than that of uniform excitation, but the damping effect of transmission tower is decreased only considering coherency loss effect.