Abstract: Based on the damping solvent extraction method(DSEM), a refined sub-regional time domain reciprocal procedure is proposed to deal with the analysis of dynamic soil-structure interaction. The radiation condition of the unbounded domain is automatically satisfied, and the frequency dependence and the convolution integral required in other algorithms in time domain are avoided. The numerical implementation of the method is given in detail. It mainly includes two parts: A precise step-by-step integration numerical algorithm for the evaluation of interaction forces of unbounded soil in time domain; The implementation of the refined sub-regional reciprocal method for the analysis of dynamic soil-structure interaction in time domain. Since the sub-regional numerical reciprocal procedure proposed in this paper is based on the sub-structure concept, it is convenient to take into account the nonlinear dynamic characteristics of general structures. Practical applications demonstrate that the proposed method is of good accuracy and feasibility.