Abstract: A novel parallel computing method for structural seismic response analysis is proposed. In the method, the simulated structure is divided into multiple substructures, and the interaction between the substructures is considered. The core of the system is ‘Coordinator’, which is used to achieve compatibility and equilibrium at boundaries. ‘Coordinator’ is equipped with an iterative algorithm based on Quasi-Newton iterations. Each substructure is treated as an independent system and only standard I/O i.e. displacements and forces at the boundaries, are used as interfaces. The seismic response of a large structural system having four towers is analyzed using the method, and the effectiveness and accuracy of the system is verified.