Abstract: In the light of the characteristics and shortcomings of tuned mass damper (TMD) and particle damper, a combined damping scheme is proposed, which organically combines the parallel single-dimensional single particle damper (PSSPD) and TMD, i.e., the composite damping system of PSSPD and TMD in parallel. Based on the in-depth analysis of its damping mechanism, the impact force between the particles and the controlled structure is equivalent to the pulse force, and the mechanical model and vibration equation of the composite damping system are established. Firstly, the combination of time domain and frequency domain method has the outstanding characteristics, such as direct solving process, no need to solve differential equations and easy to solve the dynamic response subjected to special excitation forms, so this method is used to analyze and solve the model. Then the performance parameters of the system are analyzed, and the accuracy of the mechanical model and the feasibility of the optimization method are verified. Secondly, the parameter optimization method of the composite damping system subjected to ground motions is established and its rationality and accuracy are verified. Finally, the damping mechanism, performance and damping effect of PSSPD, TMD and composite damping system are compared and analyzed. The results show that the mechanical model of composite damping system based on time-frequency domain analysis can intuitively represent its damping mechanism with high accuracy and clear solution process, and the parameter optimization analysis method is reasonable, feasible and accurate. Meanwhile, the composite damping system effectively overcomes the shortcomings of TMD and PSSPD, and has better damping effect, wider damping frequency band and stronger robustness.