Tuned mass dampers (TMD) are widely used in buildings and other structures to reduce earthquake and wind-induced vibrations. However, the application of TMD in wind turbine (WT) structures is limited. Literature shows that the TMD for WT is designed to reduce wind-induced vibrations. However, with the increased popularity of WT in seismically active regions, TMD can be effectively used to mitigate earthquake-induced vibrations. Hence, this study optimizes TMD for WT structures by considering the near-field (NF) and far-field (FF) ground motions. The numerical investigation is carried out for WT structures using OpenSees software. The nonlinear dynamic analysis is performed, and the WT structure responses are compared for multiple TMDs, single TMD and without TMD structure. The mass of TMD and locations are optimised for serviceability and limit the state of collapse.